This shrine buried deep in the jungle once held a secret, long since revealed by looters after the shrine was abandoned in a war some decades ago.
Until then, most only knew of the two chambers that made up the shrine itself: the foyer where worshippers lit incense in small alcoves on either side — still visible today — and the large inner chamber, where a shrine attendant burned sacrifices on a large altar.
After the war, looters broke into secret doors in the back and side of the inner chamber to reveal passages leading down into an extensive complex of store rooms. This easily defensible dungeon has since trade ownership many times between various monstrous tribes who would drive out squatters, only to be driven out by another tribe.
This map can easily be stocked by any monster tribe you desire. Any given room might contain treasure from past inhabitants or spoils from raids by the current owners. Rooms 5, 6, and 12 make for good treasure rooms, and the tribe’s elite will typically stay in rooms 8 through 12.