Similarly, Repeater and Red Stinger cannot handle Excavator Zombie. The player should plant a Melon-pult or an A.K.E.E. in every lane.
Spikerock can be dug up by Excavator Zombie, but it is very important in the later part of the level.
Bug Zombies can fly over plants, and they are completely invulnerable to Spikerocks. Regular ones can be killed easily but the player should watch out for the stronger variants. It is important to note that Bug Zombies carrying Conehead and Buckethead variants pose a much bigger threat than even Excavator and Parasol Zombies in lanes without their counters.
The small number next to the zombie icon means that zombie will always appear in that lane, with 1 being the topmost lane and 5 being the bottommost one.