Gate turrets: a new switch in the Setup menu, on by default. A tower stands beside every gate of the base. Walk up to it and press E to build a turret on it, then upgrade it from the same window. A tower can only be used when its lane is open.

Turret upgrades: damage, fire rate and range, up to five levels each, and a price that rises with every level. The prices follow the difficulty.

Turret weapons: every turret starts with a pistol and can be given a shotgun, a rifle, a sniper rifle, a flamethrower, a minigun or a bazooka. Buy each one once and switch between the ones you own for free, in the same window. The tower is coloured by its weapon.

The turrets never need ammo. Their kills pay gold and experience to the whole team, split between all players and bots.

Destructible turrets: a second switch in the Setup menu, off by default. When it is on, zombies attack the towers. A destroyed tower turns see-through red and stops shooting, and you repair it with the hammer. Its upgrades and weapons are kept. A new health upgrade makes it tougher.

Empty tower spots show a green ring on the ground, and a green see-through tower appears when you walk close. A tower becomes see-through when you stand behind it.

Repair option: the hammer now has Repair as its first option, and it is the one selected every time you pull the hammer out with G. Hold the left mouse button to repair. It mends the closest damaged wall or turret, or the one under your cursor if you aim at it. A green ring shows what it will repair.

Turret range upgrade: the Engineer can now also buy more range for the small turrets.

Bots and gate turrets: bots build gate turrets beside their gate, upgrade them with the weapons of their profession, and repair them when they are destroyed. Repairing a destroyed tower comes before building walls.