The crows make an appearance in every Resident Evil game except for Resident Evil: Code Veronica X, however the crows are not aggressive in Resident Evil 4. They are crows who have been infected with the T-Virus. The crows main form of attack is pecking the player, and they can also slash the player with their razor-sharp talons.
The creatures can be killed with one shot of any weapon, so if evading is impossible the handgun is your best option.
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