Just to have a go at it: 

Cherubims to heal people when the earth gets fucked over.
Guardian angels for divine transportation out of the eventual hell-hole.
Seraphim angels to assist in the physical devastation of the earth.

-sigh- I feel like I'm in school. Yknow, those kind of questions which you think you perhaps know the answers to, but end up getting them wrong.

EDIT: On the bright side, do i get brownie points for trying? Ha-ha.