Whiter the Cherubim

The Cherubim descends into the Overworld and watches the directions of the world. When a player attacks it, it can strike back at the attacker, and once that player falls below half health it is banished to the Nether. The entity avoids violence, but if it is provoked it punishes sinners directly.

Where the Cherubim stands, healing roses bloom around it, and its presence smites hellfire and turns the surrounding ground into flowers. Players can use Ender Pearls to save themselves before a banishment. A server running it needs every connecting player to have it too. It is published for Fabric only, with a single file for 1.21.1, and is licensed as All rights reserved, so it is not open source.