The Infected Giants are special Infected.
"The corrupt body of this infected person has swollen to an enormous size. Its thick skin makes it almost invulnerable to low-caliber weapons."
Giants have big hitbox and are the only unit that can't squeeze through 1-tile wide spaces.
They are deaf, and only become aggressive if they see soldiers or buildings, get damaged, or during final wave.
The Infected Giant only appears at difficulty "Medium Population (Challenging)" and higher.
In the campaign, their health varies from 4000 to 20000 depending on the difficulty.
Giants will join the final wave, so it is highly recommended to deal with them in advance.
Due to their high health pool, it is highly advised to bring a 30+ team of snipers to deal with Giants (preferably vets). Their high single target damage ensures that the Giants health goes down quickly. Attacks of Giants have huge area of effect, so It's also advised to have extra units to kite the giant:
Stone Wall has 1000 hp and can sustain 7 hits from a Giant; placing multiple pillars or a corridor of two parallel walls may distract Giant for long enough time to kill it. Common strategy involves building either a field of single-tile pillars or a corridor, using Ranger to draw Giant's attention and luring it into said structure, while Snipers deal damage to it.

However, if Giant attacks walls, units and towers should be at least 3 tiles away from outer layer of wall, otherwise Giant will reach them.
Train only deals 1600-1800 damage to Giant.
If terrain prevents Giants from reaching Command Center during final wave, they will attempt to go take straight through terrain and get stuck, as seen here.


