Enemies in Leap Day harm the player characters on contact, sending them back to their previous checkpoint. Most enemies can be killed by jumping on their heads, but they will all respawn if the player dies and restarts from a checkpoint. They also will respawn at the exact place they start the movement. Most of them follow a set pattern, moving from left to right like the player.
Pink nose enemies
Pink nose enemies have a pink spherical body and four stumpy legs, two white circular eyes and a trunk. Pink nose enemies walk back and forth continuously and turn around when encountering a wall or a drop. They will harm the player on contact but can be stumped if the player jumps on their heads. Whenever they spot the player in front of them, they will charge a snot for one second and shoot it forward. The snot will fire horizontally at a great speed but will not go through walls.
Soldiers are dark purple creatures with two short legs and arms. They carry a spear and have a round helmet covering their heads. Their helmet has hollow eyes and two teeth, making them look like skulls. Both their spear and helmet seems to be made out of a greenish metal.
Soldiers will walk back and forth on the platform they are standing on. Despite pointing their spear forward, they are harmful to the player on all sides except for their heads. Jumping on the head of a soldier will kill it, but will send its helmet sliding at a great speed. The helmet will bounce on walls and drop down when reaching the end of a platform. Jumping on the helmet again will break it.
Mushrooms have a large white stem with their face on it, as well as a pink conic cap. Mushrooms move back and forth on the platform they are standing on. They will jump every time the player does a normal jump or a wall jump, but not when the player performs a double jump. Mushrooms can only do single jumps and not double jumps. Even if they will not leave their platform with regular pathfinding, their jumping ability allows them to reach other areas. These enemies can be quite difficult to stomp, as they will jump at the same time as the player and are taller than them. For that reason, it is safer to approach a mushroom with a double jump than a regular one.
Green runners are green enemies with two small legs, two wide eyes and large pink lips. Green runners slightly resemble Green Ninja.
Green runners will move back and forth on their platforms like most enemies in the game; however, they will move much faster than normal enemies, going at around 2/3rds of the player's speed. They can be stomped on.
Stone Monsters are square stone blocks with two spikes on their left and right sides. They have a large rectangular red nose and two white eyes with purple underlines. They have a wide mouth with two white teeth. Their facial expression changes depending on what side they are on.
Stone Monsters have two flat sides and two spiky ones. They will roll on their sides every few seconds, which will make them move forward as well as changing the position of the harmful and safe sides. They will move towards the same way and will only change direction when reaching the end of a platform or a wall. Their safe side can be stood on, as well as serve as a wall the player can wall-jump from. Stone Monsters that are standing on a one-way platform with their spike sides down can harm the player below them with their spikes; however, if Stone Monsters are standing on a regular solid platform, their spikes will go through the ground.
Spring heads have a small hemispherical blue body with two feet and white eyes, as well as a large red spring on top of their head. Spring heads will move on a set pattern on the platform they are on. Touching them from the sides or from bellow will kill the player, however it is possible to jump on them. Due to the spring on their heads, it will make the player bounce upwards about as high as a normal jump followed by a double jump would. If the player jumps when landing on the spring, they will not receive an upward boost from the spring but instead perform a regular small jump.
Spike heads are a variation of spring heads, with a small pale green body, two feet, white eyes and a spike on top of their head. Unlike spring heads, spike heads serve as a moving hazard. Similarly to their spring counterpart, the spike heads move on a set pattern on the platform they are on. Touching them in any place will kill the player.
Jellyfishes have a round head with two white eyes and large circular lips, and use their tentacles to move around. There are two variants of jellyfishes: blue and red. The blue ones have a light blue and purple body with a pink mouth, while the red ones have a red and purple body with orange lips and what seems to be an orange crown or fin on top of their head. Both jellyfish types have a yellow electric field around them which constantly sparks around them.
Jellyfishes cannot be harmed due to the electricity surrounding them. They move around the area they occupy and have the ability to jump to the ceiling right above (or below) them and start walking on it, essentially changing their own gravity. Even though the electrical field around them is not animated in their jumping animation, they are still harmful to the player when jumping. Blue jellyfishes will change gravity whenever the player is above (or below) them, in an attempt to hit the protagonist in the air. Red ones, on the other hand, will change gravity every time the player does a simple jump or wall jump, in a similar fashion to mushrooms. Also like mushrooms, red jellyfishes will not jump when the player does a double jump, and can react to the player's moves regardless of their relative position.
Spike shells are round creatures with a brown body and two small legs. They have a large blue/red circular shell covering most of their body with three white spikes on it. Their shell has a visor for their two white eyes. Spike shells are able to walk on floors, ceilings and walls. They are able to drop down from the surface they are in onto another one, weather it is vertical or horizontal. However, they cannot climb onto another surface. For example, if they are on a floor, they are not able to walk up a wall in front of them, but they can drop down to a wall on the side of the platform they are in. Due to the spikes on their shells, they cannot be harmed by the player and are hazardous from all sides. The only difference between blue and red shell creatures is their speed: red shell creatures are much faster than blue.
In End Zones, both types of spike shells can be found.
Blobs are dark turquoise slime-like triangular shaped enemies with a small ball on their head and two white eyes. Blobs will jump in the air every few seconds. They are unable to move while on the ground, and can therefore only change position by jumping. Their jump is about the same height as the player's jump, much like mushrooms. They will not bounce when hitting a wall while in the air, and will instead just fall to the ground and turn around to face the opposite direction.
Pterodactyls are green, round flying creatures with a white eye, a large beak and two featherless wings. Their eggs are red with white spots. Pterodactyls will fly horizontally and move back and forth between walls. Every three seconds, they will lay an egg which will drop down at a great speed and can be stopped by platforms. Both the pterodactyls' body and eggs are harmful to the player, although it is possible to stomp pterodactyls. Since enemies can still move around and act even if they are not on screen, it is possible for a pterodactyl to lay an egg and for it to fall on top of the player without any visual or audio cue to avoid the egg.
Maggots are small creatures with a purple body, a white skull head and four tiny brown legs. Maggots are usually found in groups of three on the same platforms. They move as quickly as the green runners but are much smaller, making them harder to hit. They can be especially difficult to deal with if there are many maggots on one-way platforms the player has to traverse.
Jungle plants are wall plants with a red conic mouth that has a white eye and surrounded by a ring of green pointy leaves. Jungle Plants are the only enemy encountered on walls, on which they are able to creep up and down slowly. When they spot the player in front of them, they will stop for a second and spit out a green ball of liquid which will travel horizontally at a fast pace, in a much similar way to the snot fired by pink nose enemies. They can spot and lock on the player even if they are slightly above the protagonist's level, which means that they will not move and will constantly spit goo in an attempt to kill the player.
Large Jungle Plants
A larger variation of Jungle Plants. It shoots its tongue when the player is in their line of sight; that part of it can be walked on, serving as an additional platform. The point of the tongue has spikes. Making contact with either the spikes or the plant itself will send the player back to their last checkpoint.
Black furry creatures
Black furry creatures are large beasts with dark purple fur and two short legs. They wear a large white hemispherical skull with two purple eyes, a rectangular nose, and two small rectangular teeth. When rolling, black furry creatures will curl into a ball with their skull.
Black furry creatures are located usually in corners and stand idle. When they spot the player, they will curl into a ball and roll towards them. Their great speed along with their size makes them quite difficult to avoid. When rolling, they will drop down upon reaching the end of a platform like soldiers' helmets. They can be killed by jumping on their heads when they are idle or when rolling.
Stegosauruses are rectangular beasts with two small legs, a pointy tail and a large muzzle. They have seven purple back plates on their back. Passive stegosauruses are green and have circular plates, while aggressive stegosauruses are red and have sharp and pointy plates. When angry stegosauruses run, grey steam will come out of their snout and smoke will appear where they run.
Stegosauruses will always appear as passive, and will walk slowly on the platform they are standing on. In this state, their hitbox only includes their green body and not their backplates. They can hurt the player from the side when passive, but they can still be stomped. Once attacked, stegosauruses will become angry and turn red. Their backplates will become sharper and they will run around at a fast pace. Their hitbox will increase due to the plates now being included in it, and they will be harmful from all sides. Their size and speed when angry are comparable to the ones of black furry creatures, which makes stegosauruses very difficult to deal with, especially in narrow places.
Bombs are black metal balls with two white eyes and a mouth with sharp teeth. They have two small purple legs to stand on and a lit fuse on top of their heads. When they are about to blow up after getting stomped, they will blink red at a rapid pace.
Bombs are the fastest enemy in the game so far, going at roughly the same speed as the player. If the player comes in contact with them they will instantly explode, creating a blast half the width of the level and killing the protagonist. Jumping on the head of a bomb will result in the bomb activating and exploding in the air after one second. This enemy's speed and great explosion radius makes it a difficult enemy to deal with as they can catch the player off guard easily.
Pigs are blue pigs that have a pink nose.
Pigs are an intelligent version of green runners. They will turn around if the player lands behind them.
Ducks are yellow ducks that have pink lips.
Ducks are able to generate more ducks by laying eggs, which hatch within a few seconds of being laid. There can be four ducks at any time on the screen. All of the ducks lay eggs, and the player can defeat both of them with one hit.
Mud Monsters are covered with brown sludge. Their skin under the mud is green.
Mud Monsters can be stunned for five seconds by jumping on them. After five seconds, the monster will become normal again and walk normally.
Bats can fly and will follow the player when they are in the same area as them; they move at a slow pace.
Cactus Monsters are tall, green, cylindrical cactuses with a line of spikes on each side of their body and two small stubby feet. They have a small head which consists of two white eyes, two horns on the side, and one horn on top. Cactus Monsters walk horizontally and turn at walls. They can be encountered at different sizes, their tallest variation being the most common type encountered.
Crocodiles are either green or red and have four legs along with a purple tongue; they also have jagged mouths and two eyes. Red crocodiles have a green crown.
Crocodiles will extend their tongue out to attack when they see the player. The only difference between green and red crocodiles are their movement and attacking speed. Red crocodiles are faster in movement but slower in attacking but Green crocodiles are slow in movement but fast in attacking.
Turnips are small, orange, triangle shaped vegetables and are the size of maggots. Turnips move at the speed of bombs and are different from these enemies in that they do not explode and are smaller. Unlike maggots, they do not stick together and tend to be alone.
Fire skulls are bright orange flaming circular skulls with three teeth, a large nose, and two eyes, as well as two curved horns on the side. The skull is also glowing in a ball of fire and emitting fire particles.
Fire skulls travel diagonally through the air, and bounce at a forty-five degree angle against any surface they encounter. Much like enemies, they are not able to go through one-way platforms and instead bounce on their underside, even if these platforms can be traversed by the player. They are always limited by a specific area between two one-way platforms. They have a relatively large hitbox, which includes the ball of fire surrounding them.
The following enemy was added in the Halloween update.
Fish skeletons have a white rectangular body consisting of a few frills behind them and a fin. Their skeleton consists of a head and a torso. Their head consists of a square with a circle for their eye and three downward bumps for teeth and their torso appears as two vertical lines, the posterior one shorter than the other, and a horizontal line going straight through both.
Fish skeletons moves horizontally will pass through the wall of the stage upon encountering it and move off the stage, reappearing on the opposite side of the stage after a short period of time. They sometimes move in group of two across a single horizontal section. Fish skeletons cannot be killed.
Fish skeletons initially appeared in the Electricity theme, but in a later update became exclusive to the Spooky theme. Fish skeletons can still be seen in End Zones.
These enemies were added in the December 2016 winter update. They appear in the Ice Temple and Snow Land themes.
Woolly Trunkies are similar to pink nose creatures with exception of being surrounded in grey wool.
There are two types of Woolly Trunkies: regular Woolly Trunkies that shoot faster, and big Woolly Trunkies that shoot big snowballs which are slower but roll like barrels. Regular Woolly Trunkies move at a regular pace and will shoot a snowball at the player when they seem them. The big Woolly Trunkies does not shoot when they spot player, but instead shoot snowballs at their own pace. Woolly Trunkies will only start shooting when they are completely visible on the screen.
Ice Chargers have a rectangular ice body with a parallelogram-like shape below that has its two small purple feet. Their main body has a white triangle in it to show it is made of ice, and on one end of their body is their face, which consists of a white eye and a icy spike sticking out horizontally.
Ice Chargers cannot be killed, but they can be walked on. When they spot the player, they will rush towards them and one of the following will happen:
- They will crash into a wall and become temporarily stuck in it, taking a short amount of time to pull themselves out.
- They will encounter the edge of a platform, which will cause them to cease their rushing.
Flying diamonds are diamond-shaped creatures. They have a white circle on their body as an eye and a purple propeller above them.
Flying diamonds will hover above the ground and fall down when the player is directly below them. If there is a thin platform between them and the player, flying diamonds will not fall.
Horned monsters appear similar to the Frost Bite series' Furry creatures. However, they walk differently from the aforementioned enemies along with having a darker shade of grey for their fur, completely white eyes, and a purple nose. They have pink bottoms, which can be seen when they land on their horns.
Horned monsters cannot be harmed from the front, but can be harmed when attacked from behind, which is revealed when they try to attack by jumping and landing horns first.
The following enemies were added in the February 14, 2017 update. They appear in the Castle themes.
Archers fly in a set pattern in either a horizontal or vertical movement, or both. They can sometimes be found stationary. When the player's character is in view of an archer, with no platforms or walls obstructing it, the archer pauses its movement to draw its bow and arrow. It will aim for a brief moment before shooting the arrow towards the player's current position at the time of shooting. This arrow can kill the player's character if it makes contact.
If the player's character passes an obstacle that blocks an archer's view of the character while it is aiming, it will stop aiming and resume its movement. The arrow is only launched when the character remains in the archer's view parameter for a while and can be avoided if the player's character is moving and not turning at a wall. Archers can be killed by jumping on top of their head, but touching the arrow even when it is not launched can kill the player.
Pink blobs usually appear in the same levels as archers. They have the same physical appearance as a regular blob, except they are coloured pink and have a dark pink heart that their right eye partially overlaps with. Their behaviour is also similar to that of regular blobs, in that they leap off the ground and pause before leaping again.
When the player's character is directly in line with a pink blob, the pink blob will make a much higher leap off the ground and attempt to stomp on the character. This stomp kills the player's character on contact, and if the character is not moving constantly, it can be defeated by this attack. Like regular blobs, pink blobs are killed by jumping on the top of their head. Since the pink blob only stomps at the character's last position at the time of stomping, the character can evade this attack if it keeps moving in a straight line and not against a wall. Parts with pink blobs sometimes contain stair-like obstacles that can make evasion of their stomp attack less straightforward.
This set of enemies was added to anniversary update.
Brown circular one-eyed creatures with a blue helmet with candle on top.
Candle soldiers moves step by step and after few steps the candle on top of the helmet will ignite. The enemy can only be killed when the candle is not lit. These only appear at Fireworks theme.
The fruit bat flies around in the enclosed area. When this enemy is near some fruit, it will pause and inhale the fruit, and the enemy will fatten in the process. Any fruit the bat consumes goes towards the player if they kill the fruit bat. These enemies only in the Clocktower theme.
Yellow worms with a white head. Inside them are purple flies.
Grubs are often found above the platforms where they fall. When they explode, they release several flies. Grubs only appear in the Desert theme.
Version 11 enemies
This set of enemies was added in Version 11.
Crabs appear in the Beach themed levels. They change direction based on the player's position, and have a small cannon that shoot fish. They walk on platforms generally sectioned off so that the player does not walk on the same platform as them.
Crabs cannot be killed, but when jumped on, they will give a small boost to the player. The fish shot out of the cannon can be jumped on, which causes the fish to instantly disappear. Both the fish and crab can hurt the protagonist if touched from the sides. This enemy type is exclusive to the Beach theme.
Eels appear in the Beach themed levels. They are fixed in place from a single square shaped body, which has four holes in it. Any holes that face open space have beaks peeking out of them. The necks fully extend out in a straight direction and latch onto a surface across from them, then completely retract back into the body with the exception of the mouths. These actions alternate approximately every three seconds, and happen simultaneously, though not all of the eels will be in the same position at a given moment.
The player can walk and wall slide on the eels' necks when they are fully extended, whether horizontally or vertically. The mouths, however, are harmful at all times and kill the protagonist on contact. This behaviour is similar to that of the large jungle plants in the Forest theme, however, the eels' extension is done periodically and not initiated by the player's own interaction like the jungle plants. These enemies along with crabs are exclusive to the Beach theme.
Mr. Cloud was introduced in the December 7, 2017 level past checkpoint 15, and only appears in Windy themes. This enemy is white and has round eyes, also coloured white, as well as a purple mouth. Mr. Cloud is encountered alone within the area he is contained. Like the purple bat, his behaviour is affected by the character's position within his territory.
When the player enters an enclosed space with Mr. Cloud, he will briefly inhale and exhale, causing him to rapidly dart to the character's last known position at the time of exhaling. Mr. Cloud then turns grey and sparks lightning bolts for a quick moment before propelling himself towards the character again. This enemy kills the protagonist if jumped on, regardless of his state.
Unlike the other honing enemies and hazards in Leap Day, Mr. Cloud's movements are faster, but have pauses in between them. If the player moves the character perpendicular to Mr. Cloud's current position, they can typically dodge Mr. Cloud's attacks so long as the character keeps covering a significant amount of distance. If the player finds the character trapped in a part of the area that requires the character to move parallel to Mr. Cloud's current position, the character is generally more vulnerable. Mr. Cloud is only found in the Windmill theme.
Similar to fish skeletons, cauldron fish slither out of a cauldron and follow the character around the level. They can pass through walls and blocks, but they cannot pass through Yolk blocks. They come in small and large sizes. They cannot immediately turn but their length among confined spaces increases the likelihood of the player getting trapped. This enemy, along with fish skeletons, is found only in the Spooky theme.
Tomahawk Totems are large wooden statues that move by jumping around on their platforms. Upon detecting the player they will throw their axe towards them. The axe spins in the air and then flies back, towards the tomahawk totem. If the players is still around they will try again. Their heads can be walked on. These enemies are exclusive to the Totem theme.
Fruit Mimics are enemies that resemble the fruit that the player collects. Touching one will kill the player and send them back to the last unlocked checkpoint. Fruit Mimics come in six different forms: kiwi, strawberry, cherry, banana, orange, and apple. These enemies are only found in the Tropical theme.
Version 13 Enemies
LightbulbsLightbulbs are enemies that have a lightbulb on their head. They move like spike heads, which means they can walk on walls. They do not continue until they reach a spike. Lightbulbs are found in group of two: Red and Blue. Jumping will toggle one colour, and deactivate the other colour. When deactivated, their lightbulb will turn off, they will not move, and they are safe to pass through. Their first appearance was in the April 13, 2018 level. Touching the lightbulbs when activated will kill the player. These enemies appear in the Electricity themed levels.
Toxic Sludges are huge green blobs that are usually found in tight areas, they get around by continuously jumping in either direction, eventually going in the other if they hit a wall.
Upon death they burst into two smaller sludges. Mini sludges jump at a faster rate, which makes them fairly hard to kill.
- In the March 30th, 2015 preview for Leap Day, early versions of three enemies are seen:
- Some enemies can be seen in the audience at the start of each level.
- ↑ Nitrome on Twitter: : Whoop! Stupid Stone Monsters Selfie! Testing the just submitted #LeapDay update! , 10 Jun 16, retrieved 15 Jul 16.
- ↑ 2.0 2.1 2.2 Mat Annal on Twitter:
: Mat Annal: Messing with a new background idea for #Leapday today at work! 
Megaphantaze: What's that small triangle creature? Is it some kind of baby monster or something? I haven't seen it in actual game
Mat Annal: it was supposed to be a blob splitter so a big blob that splits after being jumped on into smaller [blobs], 14 Jun 16, retrieved 15 Jul 16.
- ↑ Nitrome on Twitter: : Mud Monsters can't be killed but can be squished...they reform so don't stick around! #LeapDay #indiedev #gamedev , 3 Apr 16, retrieved 16 Jul 16.
- ↑ Nitrome on Twitter: : Cactus Monsters can be super tall in #Leapday coming soon! #ScreenshotSaturday #indiedev #gamedev , 2 Apr 16, retrieved 23 Jul 16.
- ↑ Nitrome on Twitter: : Introducing Woolly Trunky and BIG Trunky Sr to #Leapday. [video] , 23 Dec 16, retrieved 26 Dec 16.
- ↑ Nitrome on Twitter: : Today on #Leapday Introducing the Ice Charger! ... [video] , 26 Dec 16, retrieved 26 Dec 16.
- ↑ Nitrome on Twitter: : We're aware of the horned monsters being broken on today's level that stops you getting all fruit., 11 Feb 17, retrieved 11 Feb 17.
- ↑ Nitrome on Twitter: : Mr Cloud joins the enemy gang in todays level of #Leapday ., 7 Dec 17, retrieved 11 Dec 17.
- ↑ Nitrome on Twitter: : Tomahawk Totem joins #Leapday baddies today., 10 Dec 17, retrieved 11 Dec 17.