[designate] GF Diablos
[summoning] Dark Messenger
[translation] From Greek diabolos meaning "slanderer" or "accuser". Generally translated in English into 'devil'.
[classification] Guardian Force
[magic stats] Gravity (ie. Demi) magic | Careful, he sometimes misses
[aquired from] Talk to Cid when he sends you off to Timber and he'll give you the Magic Lamp. SAVE (and I mean it!) and then select the item from your inventory and defeat him in the insuing battle. First time I played FF8 I was messing around with my items in Winhill when you only have Laguna and Kiros, and accidentally selected the Magic Lamp &_& I was not happy.
[game wise] At first glance, and judging from his name, you'd be forgiven to think that Diablos was Hades from FF7's replacement. But, you're wrong ^_^ We'll get to Doomtrain in a moment. Remember Vincent Valentine's ultimate limit break in FF7? He looks like a new and improved Chaos.
The demon summon. He looks like the arch-typical demon: black colouring, huge black bat-like wings, red highlights, talons, horned features, etc. When summoned the background turns to dark gothic colours (and I'm not sure, but does a graveyard appear?), and a huge black gravitational sphere appears in the air. Diablos descends from the ball with his wings wrapped around his body, flings his wings out, eyes the opponent, and then grabs the gravi ball with one hand and throws it at the enemy before disappearing in a storm of black bats. Nifty, huh?
[real world] How about I tell you to go read the Bible and leave it at that? Nah, just kidding ^_^ Besides, I doubt Diablos is meant to be Satan; he's just a poor misunderstood demon, yeah, that's it. Diablos that is, not the other dude.
[special abilities] Well, the number one reason you'd want this guy in game play is because he has the Enc-Half and Enc-None ability for when you don't want to get into fights. Very useful. Either that, or you'll want his Mug ability--and the only other GF that has it is Bahamut, and he's an optional GF that you don't have the chance to get until Disk 3. Trust me, Mug is damn useful, althoug if you'll have to be careful because some items can only be won from a fight, and not mugged.
[aquiring tips] Since you actually have to fight Diablos to get him on your team (and since he's a lot trickier than any of the bosses on Disk 1 or 2 I think), a few tips might be useful, neh? First off, you should fight him as soon as possible, because the higher your levels go, the higher his are and the harder it is to beat him.
[preparation] Number one: make sure all the GFs you have so far who have the HP-J ability have learned it, and try and get everyone's HP to at least over 1000. If you've been training before now for AP (as you should have been ::pointed look::), Squall's level should be in the low twenties putting him around the right HP, while everyone else is in the low teens, so give Quez to Selphie or whoever else you're bringing. On your team, make sure Selphie has learned her Full-Cure limit ability and try to get her magic stat as high as possible with Mag+20% and Mag+40% (if you've learned 'em), and it's probably a good idea to bring Zell rather than Quistis, cos his limit is a combo and unless you have a gameshark, Quistis definitely doesn't have Shockwave Pulsar yet.
[on his side] Diablos number one attack is 'Gravija', a group demi attack that chops off about three quarters of your HP--Gravija won't kill you, it's his hard hitting physical attack that he does immediately afterwards that will. Alternatively, he also casts Demi, which is a single-person gravity attack.
[the fight] Number one tip in the fight: draw Demi from Diablos and STOCK it. Do NOT draw-cast. It'll do the same damage, but you don't get the nifty benefit of the Curaga counter-attack he does if you cast Demi from your magic inventory. Selphie's the magic user and healer, so get her to draw stock and cast Demi. GFs are pretty useless against other GFs, so use limit breaks when they come up. Only use limits once before healing to full, cos Diablos'll probably physically attack the person ASAP. If you just keep attacking him and healing, it should be a pretty easy fight. Straight after the fight, equip him and make him start learning his Mug ability, ignore the other abilities for now.
[final fantasy legacy] Another summon unique to Final Fantasy VIII. At the very least, you can name him as a great reason FF8's so cool ^__^ The closest you have in FF7 is one of the knights in KOTR, and he's replaced by Atomos (of all things) in FF9. I don't know why they didn't keep Diablos, he was so cool! Seriously, a huge monster that's 90% mouth to a kick-ass demon?? Where's the competition?!