Through The Looking Glass - S2-E21
Continuity mistake: When Angel transforms into his inner beast for the first time he is seen ripping off the right leg of an Imperial guard, but in following shot the leg is intact and it stays like that for the rest of the fight. (00:25:35)
Answer: Nope, it's not Darla - that's Rachel from the episode "In The Dark", the third episode of the show (the one with Spike's magnificent opening monologue).
Tailkinker ★