The contest already has a very subjective quality to it, so the 'hard questions' are going to even themselves in people's various opinions. For people like me or OK, who are very character-centric fans, we're probably going to vote unique signature moves for PCs very highly because we like the character and our memories of the technique are tied to them. For people that prefer/respect bosses to PCs from a mechanics standpoint, they will vote boss techs higher based on their memories of how much the move decimated them. Elfboy already pointed out that we're voting on techs, not specifically characters, so if you're discussing a non-unique tech - your memories in favor of it might include something like giving it to ALL of your playable characters (this was something I did with Ultima back when I played FF6 obsessively as a child).
Another question though - does this tournament include things like the 'E. Skill' materia as one skill? If someone nominated the Diablos GF, would we have to take Mad Rush into account? WA3/5 Mediums would fall under this category too, I imagine.
And, some nominations!
AtL2 Invincible - I really like the way this works in the DL.
PS4 Saner - I have a generally love for PSs techs, but Saner stands out, and I always tie it to Rika.
FF6 Ultima - Well, I spent so much time making everyone -learn- it... Also, Fanatic's Tower boss kicked my ass with it all the time, so high boss respect, too.
FF6 Vanish - Broken with X-Zone/Break. But even when not being used exploitatively, Physical immunity + Magical suceptibility is a cool idea.
FF6 Fenrir - I just like the status effect it gives so much. Aesthetically pleasing for its time. Fond memories.
WA4 Intrude - Not broken, and still damn cool. Awesome in the DL, and tied to Raquel for extra awesome.
Disgaea Lift/Throw - Game mechanic more than tech, not sure if it counts, but it's utilized so effectively in-game. I'd like to see enemies use it every once in a while, though. Throwing Prinnies is also great fun, and as close to plot relevent as blowing up penguins ever gets.
FFT Math skill - Broken. And that makes me happy. No DL use, but damn cool in-game.
Ar Tonelico Energy Ball - Misha's version of the infinite turn-free blast of hell. Just really cool when I consider it in a turn-based system. It's a little weird to me that the AT Song Magic doesn't sound very songlike.
TotA Force Field - Unlike Tear's hymns, which are all universally aesthetically pleasing. Nomming specifically Force Field because I like temporary invincibility moves and they see a lot of use when I play games with them.
EDIT: Soul Nomad Demon Blast - The Devourlord's ultimate attack is the most stylish thing I've ever seen created using sprites. Also, strongest attack in the game?
Not sure how many noms I'm allowed, so I just nommed a bunch trying to keep the ratings axis in mind. It can be increased or reduced as necessary, but I wanted to get cracking at it!
Really like the idea!
-Djinn