User blog comment:WanderingSkull/Shell Of The Dead: Koopa Troops vs. Zombies (PvZ)/@comment-3189283-20140323185726

Lets see shall we:

Standard:

Despite being outnumbered 3-1 I have to give this to the Koopa Troop. Sure they may not be as durable or as strong but they more than make up for this with stratagy, intelligence and the fact that they have access to long range weaponry. The bullet bill turrets and Bob-omb's will do massive damage to multiple zombies at once. The basic zombies are very slow and very close range attackers and even in groups they shouldn't be able to make it close enough to actually threaten the koopa's. Even if they do those shells are pretty damn durable and they should be able to push them back, with help from the other koopa types.

Edge: Koopa Troop 

Steel Power: 

Another pretty easy edge for the koopa's. The bucket head zombies may be much more durable than the regular zombies but they are still just as stupid and close range orientated