Nightmare Geese (ナイトメア・ギース) is a character used to "replace" Geese Howard in games where he is canonically considered dead, supposedly as a literal nightmare and/or a ghost. To confirm his "nightmare" title, this version is usually more powerful than the normal Geese, and is marked by an aura of chi energy around his feet.
- Gather Chi: Geese can gather chi energy from Gaia, the mother-earth.
- Sense: Geese can sense the presence of people nearby.
- Energy Projectile: Geese can fire a wave of energy called Reppuken and even fire two of them at the same time (Double Reppuken). The air version is called Shippuken (for one shot) and Double Shippuken (for two shots).
- Energy Attack: Geese can infuse his normal attacks (punches, kicks, etc.) with chi energy to cause more damage.
- Cutting Energy: Geese can create blades of energy as seen in his Flying Solar Slash move.
- Energy Geyser: By touching the ground with his hands, Geese can make a geyser of energy come from below the ground. He called this attack Raising Storm or Raging Storm.
- Summon Thunder: With great difficulty, Geese can also summon lightning from the sky. He uses this in his Atemi Nage and Thunder Break moves.
Geese's fighting style remains unchanged.
- Geese ni Shoyu (Soy Sauce for Geese) - Real Bout Fatal Fury Special, The King of Fighters '98: Ultimate Match (as EX Geese) (both arranged versions in E Minor)
- Geese ni Mustard (Mustard for Geese) - The King of Fighters 2002: Unlimited Match
- Kiss Geese Once More - While never used explicitly for Geese, this theme is used in the "Infernal Gate" stage of both KOF: Maximum Impact and Maximum Impact 2. The stage is modeled after Geese's "throne room" from the original Fatal Fury.
- Real Bout Fatal Fury Special - hidden boss
- KOF: Maximum Impact 2 - unlockable
- KOF Maximum Impact Regulation A
- The King of Fighters 2002: Unlimited Match
- The King of Fighters 98: Ultimate Match - as EX Geese Howard