How to delete the effect particle when summoning a mob

The ShowParticles tag, when set to 0, will hide particles from that effect. The datatype of 'byte' must be declared by appending the numerical value with a "b":

/summon Creeper ~ ~1 ~ {ActiveEffects:[{Id:14,Duration:1000000,ShowParticles:0b}]}

If you aren't going to give the mob a name you can do this:

/summon Cow ~ ~ ~ {CustomName:"noeffect"}

Then:

/scoreboard objectives add noeffect dummy

Then:

/scoreboard players set @e[type=Cow] noeffect 1 {CustomName:"noeffect"}

Then:

/effect @e[score_noeffect_min=1] EFFECT SECONDS AMPLIFIER true

True makes deletes the particles.

Sure there is another way, but this works!

//dnorhoj