Blue

Blue is an enzyme and the main character of the Test Subject Blue series. He is also called Test Subject Blue or Test No. 0001232423545 by the scientist.

History
Blue started off as an experiment by a scientist in Test Subject Blue. He put Blue through 25 tests, trying to see what the enzyme was capable of. After completing all 25 tests, the scientist decided to merge a blue and orange enzyme together, thus creating the green enzyme.

From the newly created green enzyme, the scientist tested it out against Blue. When carrying out the 3rd test, the sirens within the lab went off and the scientist abruptly disappeared. Blue managed to complete this test and the scientist tried to carry out the next, but lost ahold of Blue as he injected him into the start cylinder. Once Blue approached the food pill, he was snatched by a guard of Doctor Nastidious and taken to his lab instead. Eventually, Blue would be taken to Nastidious' secured test lab and injected into another suit, seen as Rex209.

Armament
Blue performs his tests in a mechanical suit known as the Proto Suit. It allows him to shoot proton bullets for defense, and move freely around his surroundings. He is also given the ability to jump when hazards are presents. Hazards will instantly shatter and destroy his suit as well as himself. In Test Subject Arena, the suit also has a special melee account. When close to Green, he will slash the enzyme with an piece of proton extending from Blue's gun. Also when he kills Green in Test Subject arena he extends some proton and strikes a pose.

Occupation
Blue is tested out by the scientist through twenty-five tests. In each test, he is spawned and placed in his suit from a spawn cylinder. In each level, he must navigate himself to a food pill, which at the start of each level is surrounded by a glass capsule. To deactivate the glass capsule, a key card will deactivate the glass around the food pill. Blue can now obtain the food pill, which he will pick up when he gets to it and be sucked through a pipe to the next level. He may have to use other objects to get to the key card and food pill.

Test Subject Arena
Blue also makes an appearance in the spin-off Test Subject Arena, facing off against Green from the sequel. The spin-off introduces a new melee attack where when it can attack Green within a very close range. Instead of shooting with the proton gun, Blue will slash Green with an extended piece of its gun.

Nitrome Must Die
Blue appears in Nitrome Must Die as the fourth boss of the game. Blue is held by the scientist, whose hand is reaching out of the wall. He will move the enzyme in his suit vertically up and down the wall.

Phase 1
Blue attacks by simply firing his gun while the scientist moves him up and down. After having is health lowered down to a certain point (but less than half), he will strike his pose he does when he gains a kill in Test Subject Arena and cause several giant blue spheres to appear, all which will try to home in one the player. To increase chaces of survival, firing the weapon (containing bullets) destroys the blast, leaving the player's character unscathed. (This strategy of firing at projectile to avoid damage also becomes useful during the fight against the Nitrome Boss.)

Phase 2
After lowering Blue's health down to slightly less than half, he will switch into the Rex209 and fire more rapidly. All the time he is one the screen he will fire green proton bullets, only stopping when he is pulled back off the screen. After his health is depleted, the hand will move vertically up and down, then explode. After a few seconds, it will be slowly pulled off the screen.

Trivia

 * When Blue stands in one place for a set amount of time, he will throw himself up against the glass in his suit twice, creating cracks, which will quickly disappear.
 * In Test Subject Arena, Blue gains a special melee attack where he will slash Green with a piece of Proton extending from his gun. It is not known if this will be implemented into future Test Subject Blue games and the proton suit might not be used and the Rex209 might not have the weapon.
 * Although enzymes have no genders, Blue is referred to be male.
 * Blue appears in the Nitrome 2.0 skin, on the edge of a giant vat of what appears to be Orange Enzymes.
 * Although the Rex209 suit first appears in Test Subject Green, its real purpose is first seen in Nitrome Must Die.