How to Beat the Trial Spawners and Get Trident Trial Keys

Understanding the Spawners

Unlike vanilla monuments, this structure has no natural Guardian spawns. Instead, Trial Spawners inside the monuments summon Guardians, Drowned, and Elder Guardians. The two Elder Guardians that come with the monument are pre-spawned and do not respawn, so once you kill them they are gone for good. The Trial Spawners themselves are the real threat and the real prize.

Fighting the Spawner Waves

A Trial Spawner runs in waves: it summons a set of mobs, and you must defeat them before it will spawn the next set. Keep moving and use the monument's corridors to break line of sight so Drowned and Guardians do not all pile onto you at once. Elder Guardians summoned by a spawner apply Mining Fatigue, so deal with them early or your ability to break blocks and escape will suffer. Bring a Trident or a good sword with Impaling or Sharpness, and keep a bucket of milk or a way to remove Mining Fatigue if you need to dig out.

Claiming Rewards

When you finish a Trial Spawner's waves, it drops loot and sometimes Water Breathing potions, and it can drop Trident Trial Keys. Collect every key you find. Defeating the spawners is the main progression loop of the monument, so clear them systematically from the outer monuments inward toward the large central one.