Hardcore Totem Nerf is a mod for Fabric and NeoForge that aims to make Totems of Undying more suitable for hardcore worlds. It does so by applying several hardcore-inspired nerfs and debuffs to totems. Every modification is configurable, and includes:

Enforce a cooldown on totem usage
Enforce a total usage limit (disabled by default)
Reduce the player's total hearts whenever a totem is popped
- By default, a player can die from losing hearts
Restore player hearts when they consume an enchanted golden apple
- Limited to 10 total hearts by default
Disable vanilla totem buffs, including:
- Absorption
- Fire Resistance
- Regeneration
Apply debuffs fitting of someone barely brought back from the brink of death:
- Blindness
- Slowness
- Weakness
- Mining Fatigue
Limit instant health regeneration (default half of max health)
- Enable or disable player warnings for cooldowns and limits
Enable or disable player insights
- If enabled, players can view limit/cooldown settings, remaining usages, and applied cooldowns using the /htn insights command.

All of these options (and more) can be fine-tuned in config/hardcoretotemnerf.json. Additionally, thanks to MidnightLib, this can be configured in realtime using the config screen (bound to '-' by default), Mod Menu, or the /midnightconfig hardcoretotem command.

Compatible with:

Inventory Totem
Charm of Undying
Netherite Extras
Void Totem

While this was built with the hardcore game mode in mind, this would certainly fit well in non-hardcore worlds and servers as well with some configuration tweaks. When using this mod outside of hardcore difficulty in some 1.20.x versions, it may be worth including a mod that preserves player attributes on respawn.