Here was my guess, knowing you've often marveled at how people say D&D combat lags, so I figure your group whipped through things quickly (not that it was easy, just that combat moved!)
* 12 Hobgoblin (Ftr 2), 1 Hobgoblin (Clr 5), 2 hellhound, 1 Hobgoblin (Ftr 4) (20 minutes, lots of stuff...