Infinite Corrosion Form, Death Army Cosmo Lord

(This ability is active if you have four or more damage): 2 all of your Nova Grappler rear-guards. If four or more units this way, this unit gets +1 until end of turn. This ability cannot be used for the rest of that turn. :[Choose two of your rear-guards with "Death Army" in its card name, and them] This unit gets +5000 until end of turn.