In the current snapshot, there appears to be an issue where Ocean Monuments are improperly spawning Normal Guardians. All three Elder Guardians spawn correctly.
This was tested and confirmed with two newly generated Ocean Monuments.
Potential Cause: Changes made to the maximum light level at which mobs can spawn resulting in the area around the monument not meeting the conditions to spawn guardians?
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We're tracking this issue in MC-237986, so this ticket is being resolved and linked as a duplicate.
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