Grims should not be able to attack event mobs, nametagged mobs, or (player made) event serum mobs

As for the event mobs, it’s been made clear in the discord that they don’t drop exp when killed by a grim in order to prevent afk exp farming. However, this isn’t apparent to a lot of casual players, who would innocently use the spirit armor/sword while exploring the open world, and may not even realize that they aren’t gaining exp from it. The grims shouldn’t target these mobs altogether, in order to prevent confusion and frustration.

As for the nametagged mobs, I often have mobs on display which has made me require my realm members to never wear spirit armor or use a spirit sword so that they don’t accidentally kill them. If someone nametags a mob, you can safely assume 99% of the time they want to keep that mob alive and that a grim killing them would be accidental. It would be especially frustrating for it to happen to something like a zombie villager or legacy jack o lantern/santa hat mob. The same goes for event serum mobs. If a player uses event serum on something, you can presume that they want to keep it alive for display purposes.