Yeah, it's Nature's Release. Basically, anyone who crits them can heal 4 or 5 hitpoints. It's supposed to represent the natural world's satisfaction at having the strange, alien frogmen thwacked.
Because PCs bullywugs are "reformed," I probably won't make it so that enemies benefit from critting bullywugs. Perhaps the ancestors of PC bullywugs made an agreement with the primal spirits or something. However, having something happen when they crit or when someone crits them might be cool. I might be tempted to make a feat out of it if we can't make a good racial ability out of it.