Dark Sector A glaive grows from your arm

The Technocyte virus does not just try to kill Hayden. It gives him a three-bladed throwing weapon he grows from his own arm, and it is the best thing in the game. You hurl it across a room, steer it in flight to curve around cover, and watch it come back slick. As the infection progresses the glaive evolves: charge it with fire, electricity or ice to burn through obstacles, shock enemies behind walls, or detonate it mid-flight. It solves puzzles as readily as it solves people, and throwing it never stops being satisfying. Guns are here too, but the glaive is the reason this game is remembered.

Here is the twist that keeps shooting interesting: enemy weapons carry governors, inhibitors that stop anyone carrying the mutagen from using them. Grab a fallen soldier's rifle and you get roughly ten seconds of firing before it dies in your hands. The workaround is the black market, where you buy and upgrade clean weapons with the governors removed. Ammo stays scarce, so every fight becomes a decision: spend bullets, or spend the glaive. It turns what could be a standard cover shooter into a constant resource puzzle, and the upgrades make the guns you keep genuinely worth keeping.