Four Concealed Pungs 四暗刻

Why it counts

Every triplet built from your own draws, nothing claimed from anyone. Won on a discard, that tile must complete the PAIR. A discard finishing the fourth triplet makes that set claimed, and the hand is merely All Pungs.

Stacks with

Absorbs All Pungs and Concealed Hand, since it is both by definition, but stacks with a flush, so a single-suit version reaches the cap.