I like having the Onaquis hang back and just research or summon. The auto generate sacred bats things is awesome, especially if you park them in high dominion. Backed by a nice bless (say F9) those bats are nasty and they an ugly surprise to someone who wasn't expecting Mictlan to show up with flying sacreds.
I've won some big battles I shouldn't have in MP because I had a squad of those bats set to hold and attack archers. They got in the backfield, ate all the archers, and then ate all the commanders for routeriffic goodness
