The combination of Barrel Roller Zombie and Imp Cannon pose a huge threat, as defeating both efficiently of them requires different methods of attack. Therefore, the player should pay attention and deal with the zombies accordingly. In addition, there are some Swashbuckler Zombies and some Seagull Zombies. Kernel-pult and Snapdragon are recommended, as they can efficiently take both of these zombies down. Other than that, the player has no objectives to complete, and is just a regular level, which the player shouldn't have much of a problem with.
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.
Only at different points are these zombies are much more dangerous. Using the Spring Bean's Plant Food Upgrade is the best choice against them.
The Bloomerang is also a good choice to deal with the Barrel Roller Zombies, as it will kill the zombie rolling the barrel, instead of the barrel itself and it is also good to deal with Imp Cannons. Timed just right, putting Plant Food on Spring Bean, then combining the effect with Blover will instantly blow away all zombies on screen (except Imp Cannons).