The crossword-style answer for “action in the card game Egyptian Rat Screw” is SLAP.

Why “slap” fits

In Egyptian Rat Screw (also called Egyptian Ratscrew or Egyptian Rat Slap), players try to win the central pile of cards by quickly slapping the pile when certain patterns appear (like doubles, sandwiches, or other agreed‑upon combinations). This slapping action is so central to the game that many people use “rat slap” as an alternate name, which is why “SLAP” is the standard clue answer.