Ominous Trial Key

The ominous trial key, a type of trial key which can be acquired during ominous events, is an item used to open an ominous vault to get rare loot, such as the heavy core, an ingredient used in the crafting of a mace. A regular vault and an ominous vault may only be unlocked once per player.
==Use==
An ominous trial key is used in an ominous event from the exploration of the trial chambers.Minecraft.net - INTRODUCING THE MACE AND OMINOUS EVENTS - Test a new weapon, a new challenge, and more 1.21 features! The player needs to get a potion of the bad omen status effect first because the bad omen status effect may be obtained by consuming the ominous bottle, a type of magical potion. This bottle is obtained when the player kills a raid illager captain outside of a raid or from regular vaults. 
Being affected by the bad omen status effect allows a player to start the ominous event. Because the bad omen is a status effect, it is removed by drinking a milk bucket or dying. A trial spawner becomes an ominous trial spawner when the player gets close with the bad omen effect. An ominous trial spawner is harder to deal with and contains better loot. The bad omen status effect lasts for 15 minutes multiplied by its level. Defeating an ominous trial monster spawner allows the player to obtain an ominous trial key. The loot from an ominous vault - that was opened with the key - include unique smithing patterns and the heavy core item needed to craft a mace, a rare weapon.
==References==