First, go to either Team Attack or Single Attack Challenge mode. Beat one opponent/team, then let yourself get knocked out. Repeat this method ten times, and BOOM!, they're unlocked.
I discovered this on my own a couple months ago and did not find this trick anywhere on Gamefaqs, Gamewinners, or any other cheat site. I haven't tried this method out in Time Attack mode, so feel free to see if losing 150 times unlocks anything.
You might want to try this same method out on SvC Chaos, KOF 2003, and KOF Neowave, just to see if anything happens.
I discovered this on my own a couple months ago and did not find this trick anywhere on Gamefaqs, Gamewinners, or any other cheat site. I haven't tried this method out in Time Attack mode, so feel free to see if losing 150 times unlocks anything.
You might want to try this same method out on SvC Chaos, KOF 2003, and KOF Neowave, just to see if anything happens.