Continuity mistake: After Genos burns the swarm, it burns off Saitama's clothes, a sign falls down and covers Saitama's genitals in censoring. When the camera angle changes to behind him, the sign disappears.
Continuity mistake: When we first see Jigen on the cross, his shirt has one button left. They toss the bucket of water on him, and the shirt is now totally open. Later in the episode, when Lupin frees him, it's the other way around; the shot from the archway with the agent looking for Lupin shows Jigen in the background with the shirt open, but it's buttoned when his friend unlocks the shackle. (00:03:45)