Boss fights typically work as a one-on-one battle: in most games, players will tear through hundreds of lesser enemies, only to fight a larger enemy that's a lot tougher than its allies. Resident Evil works in a similar manner, but it makes some major tweaks to the formula: not only are the 'regular' enemies a threat, but bosses can annihilate players at a moment's notice.
So, how can you take that formula and make it even tougher? Why not put the boss up in the air, or surround it with smaller enemies? Why not do both?
That seems to be what Capcom was going for with Resident Evil 0's third boss fight, the Church Bat: not only are players forced to go one-on-one with a massive flying rodent, but its smaller, more obnoxious allies will join the fight to give it cover. It's one of the few fights in the game that can be an actual challenge - especially if you stumble onto the fight earlier than expected.
Don't worry - with a little preparation (and some serious firepower), the Church Bat will be grounded...permanently.
Thankfully, the frustration caused by a bad lock-on system and warped perspective are somewhat alleviated by the nearby checkpoint - if you happen to die, just reload and try again!
If you've been having trouble with Resident Evil 0's earlier fights, you can check out our guides to the Giant Scorpion and Centurion boss fights - and make sure to read our review of Capcom's latest HD remaster!
