User blog comment:Milesprower2/Big Discovery!/@comment-3398859-20131028160220/@comment-5792287-20131028160527

Yeah, we already knew Zomboss is back because of a scene at the end of the Wild West.

My theory of Power Tiles is that they improve a plant in some way, perhaps doubling speed or making Plant Food effects more powerful.

Citron's balls of plasma are probably just a high-power single shot attack, like a Melon with no splash or something.

Look elsewhere on the page and you can see info about the zombies, many of which use machinary or vehicles.

I also guessed the effect of Magnifying Grass being something to do with spending sun to use an attack.