Rats, Bats & Vats by Dave Freer and Eric Flint

 I think that Freer couldn't quite make up his mind what he was trying to write with Rats, Bats & Vats. It tries to be a serious war novel like The Forever War or Old Man's War, but reads like Bill, the Galactic Hero, more of a satirical work, as we tunnel and trudge through the battles against the alien M'agh with Sergeant Chip Connolly and his squad of seriously deranged genetically engineered rats and bats.

Unfortunately, the humor wasn't enough to save it, and the warfare wasn't intense enough to keep my attention. Gave it up about a quarter of the way through.