Defence light 
Possible Target Types: SELF, ALLIES, VARIANT
Trigger actions: Getting attacked
BottledLight ingredient: minecraft:turtle_scute (just scute pre-1.20.5)
Conditions:
SELF:Low Health,Very low Health,Low armor durability,SurroundedALLIES:Ally's low Health,Very low Health,Ally low armor durability,SurroundedVARIANT:Passive mob low Health
Effect:
SELF: When activated, the player will receive a Resistance status effect, with power and duration equal to the player's power multiplier and duration attributes. Particles of Defence light will spawn around the player.ALLIES: When activated, any nearby allies with low health (or not, configurable in the config) will receive a Defence status effect, with power and duration equal to the player's power multiplier and duration attributes. The player will instead receive the same status effect but with the power reduced (configurable). Particles of Defence light will spawn around the player and allies.VARIANT: When activated, any passive mob nearby, and the player if they are on very low health, will receive a Resistance status effect, with power and duration equal to the player's power multiplier and duration attributes. Particles of Defence light will spawn around the player.
Show Images

A little old Demo video
Trivia: This was the first light to receive the particle/logo in development!