A player on reddit noticed that when a clientside ghost block is obstructing the arena, Botania won't tell you where it is: https://www.reddit.com/r/feedthebeast/comments/bvb9l0/gaia_guardian_not_spawning_help_project_ozone_3/

Solution: Do all the arena prespawning checks on the server side only; upon failure just send a packet to the player

This issue is stale because it has been open for a while with no activity. Remove stale label or comment or this will be closed soon.