Waves are one of the attacks used by Zebak during the fight with him within the Tombs of Amascut. Zebak will throw jars and poison before slamming his tail, causing boulders to drop from one direction and cause a tidal wave to sweep from that side of the arena.
Much like Galvek's tsunami, players must avoid these tidal waves; getting caught by one will push the player down the direction it was going and deal moderate damage. The waves will also push jars down if they collide into one.
Zebak using his tidal wave attack.
If players are suffering from Zebak's bleed effect, they will leave behind temporary splatters of blood in their path. Should a wave wash over these splatters, they will become Bloody Waves; blood splatters that are always present in the north and south edges of the room also transform the waves.