You can, but only if you haven't done the Wutai Pagoda side-quest all the way. Godo, the last boss in the Pagoda, uses Trine, and it's accessible on any disc. But this fight only happens once, so if you already did it, you're out of luck. --- http://i33.tinypic.com/25archy.gif "I don't want to be more like my father. Being like my father got my father killed." - Concordat, Star Fox 64 LP
Trine's pretty useless at this point anyways. It was already weaker than Aqualung and Beta, the slightly better MP cost isn't that useful anymore, there's not many things left weak to Lightning that I recall, and most of what was post-Highwind didn't half/nullify/absorb other elements, making Magic Breath a much better choice (Carry Armor and Eagle Gun for instance).
All in all, getting Trine on all E. Skills should only concern those going for a Perfect Game, I myself generally prefer to have Leviathan while it's still useful. --- "One toot on this whistle will take you to a far away land." -Toad, SMB3
Yeah I am working on a semi-perfect game. So far I have all the easy stuff, and am 100k AP away from having my second master KoR to go get another Master Summon. Then I'll go kill off Emerald and get a third of each. Already have to magic and command. I am debating on whether or not I want to max my stats or not. I'm not sure I like the scenery in the Gelnika well enough to wanna spend the next few weeks farming sources down there or not.
Anyway though, I was asking because its the only skill missing off my third enemy skill materia.
It's always technically more powerful, but not nearly as spammable. Leviathan 4 11/6X Base Power and costs 78 MP, while Aqualung is 3 1/4X Base Power but only 34 MP. And of course Leviathan is subject standard Summon usage limitations and also not reflectable (sometimes good, but not reflect-abusable if you like doing that).
I also get amusement out of using Leviathan to make one more person invincible during Jenova LIFE, but that's far from important.
And for what little it's worth, as a summon Leviathan can never miss. However, the enemies that can dodge any magic even from low level characters in this game are few and far between.
Basically, like any summon until late game, it is powerful but not mid-game breaking like the Aqualung/Beta/Trine combo (or pretty much any of the useful E. Skills for that matter). All in all, its good for a hit to a boss during the point its still a powerful enough Summon to still be using, which if you only equip one Summon at a time, that would be until you've gotten Neo Bahamut (assuming you didn't miss Alexander). --- "One toot on this whistle will take you to a far away land." -Toad, SMB3