Decay loves to degrade. He loves corrosive things, erosion and basically anything that makes things die slowly, and painfully. This is why he chose to assist Vanadus; they both enjoy seeing forces of nature get to work and destroy the Tank Empire without raising a finger.
Decay is a greyish blue tank with black arms and circle hands the same shade of blue as his body. He has a large black Viking helmet decorated with a single bright blue gem on it. He, like all other members of the Squadron of Insanity, has 2 weapons, one melee and one ranged.
Decay's ranged weapon is named the Rust Musket, and inflicts a unique debuff used by Decay and only Decay: Oxidizing. Entities inflicted with Oxidizing get +10% damage received, -10% damage dealt and -10% movement speed for every second Oxidizing is in effect. The damage done reduced/damage taken increased/speed decreased is always taken from the original value, not the new, nerfed value. After the Oxidizing period ends, the effects won't immediately stop like Broken or Blinded do, but instead slowly wear off, undoing what it did over the same amount of time. That means if one gets inflicted with Oxidizing for 5 seconds, when Oxidizing wears off, he/she/it will get -50% damage done, then -40% after a second, and so on. The Rust Musket's shots inflict Oxidizing for 7 seconds unless otherwise specified, and do light damage.
Decay's melee weapon is named the Acid Axe, and is much less complicated than the Rust Musket, simply inflicting a random debuff for 30 seconds on hit EXCEPT Oxidizing. It does hit much, much harder than the Rust Musket though.
Like all other members of the Squadron of Insanity, Decay has a pre-battle phase, in which he is Invulnerable. What players actually do in this phase varies greatly between each member; for Decay, he spawns somewhere near the center of Vallard Wastes, surrounded by a huge heap of toxic waste that he constantly summons through conjured portals and maintains.
What players have to do, is that they must destroy the pile of toxic waste that surrounds Decay. This is not an easy feat, as the heap of waste consists of 60 individual pieces of waste piled in a ring that have 1500 health each. Every 30 seconds, a piece is summoned in by Decay, and piled on a spot where the waste is least concentrated. If a path is cleared, Decay will shoot at tanks with his gun, firing a volley of 15 Gunner bullets from it. If he chooses to shoot at tanks, then the conjuring of toxic waste will be slowed down to conjuring a piece of waste every 40 seconds instead of 30.
Once the ring of waste has been more than 60% cleared, Decay disintegrates the rest of the waste, and begins the fight by performing a very high leap over the tanks, doing a few flips and shooting at tanks whilst still in the air. Once he lands, he loses Invulnerable and starts using attacks from his attack pool, listed below.
- Rust Blast: Shoots out volleys of Gunner Bullets from his gun, 10 at a time. Most commonly used attack.
- Acid Shield: Uses his axe to block bullets fired at him and cleave Drones and Traps. The Acid Axe destroys drones and traps on contact, and deflects 50% of bullets fired at it. The other 50% is let through, though they only deal 75% of normal damage.
- Waste Launch: Summons a piece of toxic waste (using the same texture as the waste seen in the pre-battle phase) and tosses it at tanks. Said piece of toxic waste explodes into green goo once it hits the ground, and tanks coming into contact with it will receive a random debuff that is NOT Oxidizing, Burning, and Waterflame.
- Sandstorm: Shoots out TONS of tiny, tiny Drones from his gun. They surround Decay for a small while, before flying out in all directions. Each individual Drone does pathetic damage, but it can accumulate very quickly, considering the sheer amount of Drones.
- Neutralization: Swings his axe around for a while before tossing it at a bunch of tanks. Then, when the axe lands on the floor and does damage to tanks near the impact zone, he shoots a blast of blue liquid at it. Upon coming into contact with the Acid Axe, the blue liquid explodes into a ring of 16 bullets that do mediocre damage. Decay then rushes over, picks up his axe and keeps battling as usual.
- Cosmic Rust: Summons in a piece of toxic waste, then shoots at it with his gun. The piece of waste will start rusting, and while it is doing that, Decay will toss it at tanks. Tanks hit will receive Oxidizing for 15 seconds.
- Smoke Snipe: Shoots an INCREDIBLY fast bullet from his gun that targets the area with the most tanks. The bullet, upon impact, explodes into a large area of black smoke that gives Blinded, Broken, and Weakened to tanks in it.
- Gun Jam: Shoots a volley of 20 bullets at tanks. These bullets will not do much damage, but instead inflict Stunned for 30 seconds.
When Decay hits 15000 health, he enters his second battle phase, where, like all other members of the Squadron of Insanity, he loses one of his weapons and gains a major buff in one of his aspects. In Decay's case, his axe cracks and shatters, and Decay gets a +100% boost in agility, now having a 50% chance to evade attacks and not take damage. His attacks similarly become more movement-based and range-based, as opposed to damage-based. He also uses toxic waste in a lot of his attacks now, in order to stall.
- Rust Blast II: Shoots out volleys of Gunner Bullets from his gun, 15 at a time. Most commonly used attack.
- Sandstorm II: Shoots out TONS of tiny, tiny Drones from his gun. They surround Decay for a small while, before flying out in all directions. Each individual Drone does pathetic damage (though a bit more than in phase 1), but it can accumulate very quickly, considering the sheer amount of Drones.
- Cosmic Rust II: Summons in a piece of toxic waste, then shoots at it with his gun. The piece of waste will start rusting, and while it is doing that, Decay will toss it at tanks. Tanks hit will receive Oxidizing for 20 seconds.
- Smoke Snipe II: Shoots 3 INCREDIBLY fast bullets from his gun that targets the area with the most tanks. The bullets, upon impact, explodes into a large area of black smoke that gives Blinded, Broken, and Weakened to tanks in it.
- Gun Jam II: Shoots a volley of 20 bullets at tanks. These bullets will not do much damage, but instead inflict Stunned for 40 seconds.
- Leap: Jumps over tanks while shooting at them, 10 Gunner bullets at a time. Simple, while effective.
- Toxic Toss: Summons 3 pieces of toxic waste, then tosses them at tanks one by one. They emit radiation that gives random debuffs if entered, EXCEPT for Oxidizing, Burning or Waterflame. Each piece of waste has 1500 health, and can be destroyed, but will explode upon destruction.
- Waste Wall: Summons 10 pieces of waste that forms a ring around tanks. Each piece has 2000 health and does not inflict debuffs or damage.
- High Ground: Conjures a giant pile of toxic waste that has a total health of 7500. Decay then climbs on the pile and starts shooting at tanks from above the pile. Decay stands too tall to be hit, and the pile of waste must be destroyed in order for the battle to continue. Once the pile is destroyed, Decay immediately uses...
- Rust Smash: Decay jumps into the air, takes off his helmet while still in the air, and just before he lands, he holds his helmet under him, horns facing down. Decay then smashes into the ground, doing heavy damage and inflicting Oxidizing to nearby tanks for 20 seconds.
- Gold Plastic Syndrome: Shoves a golden ball into the barrel of his gun, then fires it out at tanks. Tanks hit won't receive Oxidizing, but instead have all their health reduced to 1, guaranteed. This lasts for 15 seconds.
- PhotoDecay: The gem on Decay's helmet starts to glow with an intense blue light, and all tanks get a random Debuff for 15 seconds.
Upon reaching 0 health, Decay will grind to a halt as cracks start forming all over him. He salutes the players, and grabs his Rust Musket and proceeds to blast himself in the head, causing it to explode. A few seconds later, his remains disappear, regenerating in the Void to fight another day...
Decay, the second time you encounter him, will constantly emit a large Oxidizing aura around him that only affects tanks. Like the others, he starts off with double health, all his attacks and no Phase 2. His death animation is slightly altered; After he shoots himself, he explodes into a large cloud of smoke that inflicts Oxidizing for the duration of time you are in it, plus 10 seconds.
- The only boss to use a unique debuff for himself.