I mean DOOM would be fitting, but the sizes of those objects don't match at all. At least if those are meant to be the pebbles that we call Mars' moons. That collision looks more like they pulled in something like Pallas and Vesta from the asteroid belt (and even those would still be a bit too small)...
Well, at least the planetary surface will be "a bit" warmer for a while now... (if you like to walk on molten rock).
For what it's worth, as a moon orbiting inside the synchronous orbit radius, Phobos is already being cranked in by tidal interactions with Mars. Several tens of millions of years from now it will cross the roche limit, and be destroyed.
