The name is all caps is what you type it is case insensitive but the spelling of it has to be mathched 
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ABSORPTION:
Increases the maximum health of an entity with health that cannot be regenerated, but is refilled every 30 seconds.
BLINDNESS:
Blinds an entity.
CONFUSION:
(Nausea) Warps vision on the client.
DAMAGE_RESISTANCE:
(Resistance) Decreases damage dealt to an entity.
FAST_DIGGING:
(Haste) Increases dig speed.
FIRE_RESISTANCE:
Stops fire damage.
HARM:
Hurts an entity.
HEAL:
Heals an entity.
HEALTH_BOOST:
Increases the maximum health of an entity.
HUNGER:
Increases hunger.
INCREASE_DAMAGE:
(Strength) Increases damage dealt.
INVISIBILITY:
Grants invisibility.
JUMP:
Increases jump height.
NIGHT_VISION:
Allows an entity to see in the dark.
POISON:
Deals damage to an entity over time.
REGENERATION:
Regenerates health.
SATURATION:
Increases the food level of an entity each tick.
SLOW:
Decreases movement speed.
SLOW_DIGGING:
(Mining Fatigue) Decreases dig speed.
SPEED:
Increases movement speed.
WATER_BREATHING:
Allows breathing underwater.
WEAKNESS:
Decreases damage dealt by an entity.
WITHER:
Deals damage to an entity over time and gives the health to the shooter.
