STATUS: Zer0 is a top-down shooter where every enemy is painted in one or even more of six colors, and only a weapon of the same color can damage it.
STATUS: Zer0 is an ideological successor of the Alien Shooter games with one crucial difference - enemies cannot be damaged by any weapon, but only expected.
It requires players to use all their six type of weapons and update every, not just one late game gun.
Enemies are not so simple - they have champions who have two different colors health bars, chameleons, who change their color in a short period, and uncolored enemies, who are invulnerable until they colored.
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Color differentiation of enemies, every color and enemy tier have its own special mechanics and parameters;
No useless weapons during the whole game;
Multikill/rage - kill streaks grants new additional mechanic depends on equipped weapon;
Multiplayer in general and multiplayer campaign that is different with singleplayer in particular;
Puzzles that can be solved with colors also.