Fangers - an update to bats

Bats are a technically useless mob in the game right now, and I feel there’s a lot of potential for an overhaul. My idea is to introduce a new mob called Fangers.

Spawning:
Fangers spawn (with a smoke effect?) from (white?) bats if they fly near a player. They are a hostile mob reminiscent of a vampire.

(They could possibly have their own dungeon called a sarcophagus, from which they are more likely to spawn? These grave dungeons can have a coffin and also a loot chest in them).

Abilities:
When damaged by a Fanger, the player gains temporary night vision (useful for mining) and slowness. Night vision lasts longer.

For around 30 seconds after being hurt, the player will burn on exposure to sunlight. This can be prevented by wearing a full suit of armour.

Fangers also have the unique ability to regenerate their own health by leeching health from the player, little by little, thus making them harder to kill.

Drops:
1 Rotten Flesh.

2 Fangs (rare drop): used to craft a potion of leeching that lets a player slowly gain health from any mob or player they attack for a short duration OR they could be combined with weapons to have the same effect but nerfed.Fangs can be crafted into crushed fangs (like bonemeal) which on consumption gives temporary night vision.

Misc:
Fangers are an undead mob.

Fangs are a rare drop like tridents.

Fangers transform back into bats and try to flee when their health is low.

This incentivises bat farms.

Leeching potions add a new twist to both PvP and PvE.