Mystery to all, this is one of those Special Pokemon that comes once in a lifetime, this lil' baby appears in the Lake of Rage on Wednesdays only. So look for him (this is a myth so don't go around your town asking have you seen Killer Jigglypuff miss?) Don't do that.

the story:
A Fire Type Jigglypuff that has the means to learn Horn Drill, Burner (an Un-Offiical Ability), and Fire Blast. At the Lake of Rage, Killer Jigglypuff can be found either at the bottom of the Lake, at the North of the Lake, or at the center of the Lake floating atop. You can tell it's Killer Jigglypuff b/c of the distinctive look on it's face & it's hair peice is in a shape of a Horn. This Jigglypuff is very hostile and well rounded for a Jigglypuff, so take care when approching this Fire/Normal Typed Pokemon. It's meaner than 5 Gyarados breathing down your neck or 8 Mewtwo's using Psychic on a human being!!!!!!! Killer Jigglypufflikes to kill Pokemon. Keep away from it's Horn, it's longer than a Seaking's nad it's Horn Drill is great for Long Range capability as well. Go into this catching sequence as if you are catching Celebi.

Killer Jigglypuff's stats:
2.2.3.2.2.2

Title:
"RED & READY"

Abilities: (~=can't learn, -=automatically acquires, ##=what level it is learned)
Sing_____-_-_-
Charm____-
Defense Curl_____4_4_-
Pound_____9_9
Horn Drill_____11_11
Sweet Kiss_____14
Disable_____~_14_-
Rollout_____~_19
Fireblast_____~_23
Doubleslap_____~_24_-
Rest_____~_29
Body Slam_____~_34
Double-Edge_____~_39
Burner_____~_~_28

And when Killer Jigglypuff is turned into a Wigglytuff with a Moon Stone, it turns into Killer Wigglytuff!!!!!!!!!!!!!