The entirety of the brothers' hit against the Chinese heroin dealers.
Connor: That's heroin.
Murphy: [pause] How the fuck would you know?
Connor: Fuck you, I know shit!
The scene in the strip club in the first film, especially Rocco's "tit thing."
Connor: What the fuck're ya doin'?
Rocco: I'll tip her!
Connor and Murphy messing with "Jaffar" on his first big job.
Paul Smecker at one point in the film suggests, "This could be the start of the first international mob war." A few minutes later, his brilliant little theory is proven wrong.
Shortly after Smecker has gone into a confessional (while drunk), Rocco has followed him in with intent to kill despite the McManus brothers' wishes. He holds the priest in the confessional at gunpoint. This is the last straw—Connor reaches through the other confessional and holds Rocco at gunpoint so that the priest doesn't get hurt. Meanwhile this exchange between Smecker and the priest occurs:
Priest: (still concerned for his life) Would they ever harm an innocent person for any reason?
Smecker: No, they would never do that. Well — the two Irish guys wouldn't, the Italian guy, he might, he's kind of an idiot.
The deleted scene from the first movie where Connor and Murphy get a call from their mother.