"Alex's primary superpower is his ability to shapeshift, changing his form to suit his needs. Going hand in hand with this power is his ability to "consume" others, absorbing them in their entirety. This process allows Alex to quickly regain health by absorbing the biomass of his enemies. This also allows him to take on the forms of the enemies he absorbs, thereby allowing the player to move about the enemy as one of them. The disguise will only last as long as Alex remains inconspicuous. Alex has super-strength, and will kill most humans in a single punch. He can perform various melee attacks without shapeshifting, as well as more gymnastic moves such as air combos, sliding along the ground using any human enemy's body, and a high-speed rolling cannonball attack.

Alex can also transform parts of his body into a selection of martial implements acquired over the course of the game, either as purchased 'upgrades' or being given them. Offensive powers include the large and powerful Blade, fast razor-sharp Claws (which can also erupt large spikes from the ground), the telescoping Whipfist, Musclemass that augments his strength, and the slow but powerful Hammerfists. Defensive options consist of a large Shield that needs to regenerate after excessive damage, and a full-body Armor that exchanges agility and speed for sheer toughness; both will allow Alex to plow through most obstacles when active. Vision modes include thermal, which allows Alex to see enemies through smoke and other obstacles, and Infected, which highlights those infected with the virus as well as military units. One defensive and offensive power may be active at a time, and using either will negate Alex's current disguise. In addition to his own abilities, Alex can take the weapons from defeated or absorbed enemies. These include automatic rifles, grenade launchers, and missile launchers. He can also seize control of military vehicles, such as tanks and helicopters.

Alex's most powerful attacks are the Devastators, which...