The Platinum Match is an arena match against Sephiroth at the Olympus Coliseum in Kingdom Hearts[a] and its Final Mix version. It becomes available after sealing the Final Keyhole at Hollow Bastion, and has to be fought with Sora alone. Originally it gave no reward upon its completion, although this changed in the Final Mix version, wherein Sora gains the One-Winged Angel Keyblade and Ansem's Report 12.
Actually attempting it should not be done until at least level 65 or so, if not higher depending on your difficulty level. The best accessories and several Elixir should be equipped as well, along with the Ultima Weapon Keyblade. In terms of Magic you should rely on Curaga and Aeroga, everything else is ineffective. If you do not have the best possible accessories then you can still somewhat reduce his damage output by equipping those that reduce fire and dark elemental damage.
In terms of abilities it varies depending on the game version. In the original both Strike Raid and Ars Arcanum are useful—albeit costly—abilities to deal damage to Sephiroth without risking your own HP too much. In the Final Mix release Sora possesses a multitude of very powerful and effective combat abilities such as Sliding Dash, Slapshot, Hurricane Blast, Combo Master, and Zantetsuken as all very effective moves. Especially Leaf Bracer is incredibly useful.
Sephiroth will mostly walk around at first, sometimes quickly dashing forward to lash out, followed by dashing backwards again. He does not deal that much damage, but he can be hard to hit and has a massive range due to the length of his weapon. He will also periodically summon three pillars of fire, damaging anything around him. After his purple health bar has been depleted he will enter the second phase, which is when he also begins to use 'Heartless Angel'. He will prepare the ability for a moment, and then cast it upon you, lowering your MP to zero and your HP to only one. He will then follow this up by rushing you for a melee strike. Either interrupt him by rushing him with Superglide, or Sliding Dash preferably, or get as far away as possible and instantly use an Elixir to recover. If interrupted he instantly counters with the fire attack.
Other than the above, he will also frequently teleport, only to appear behind you for a quick strike, and run around instead of walk slowly. Eventually he will use another notable attack, signified by the area darkening, followed by Sephiroth making multiple successive strikes on your position. He will attack very quickly, eventually finishing with an air-to-ground attack that creates a shockwave. Either use Strike Raid or rely on Leaf Bracer for either's invincibility frames.
When he is down to just his yellow health bar he will shroud himself in a dark aura (his attacks gain the dark element too) and start to use 'Supernova'. He does this moving to the center of the arena, after which a series of meteors land on the floor, creating shockwaves. They then rotate around him, forcing you to dodge and weave between the floating meteors. Meanwhile Sephiroth will be quickly enlarging the glowing sphere above him, which he throws at you when the rocks vanish. Either use an ability with temporary invincibility or avoid it with a well-timed Dodge Roll, as it deals a lot of damage.
He will now also use various fast spinning attacks while sending out waves of dark orbs with each attack. He can also summon them around you, after which they quickly close in. At this point you are close to finishing him off, and all you need to do is be wary of another Heartless Angel or Supernova attack. Although he will be difficult, relying on abilities with invincibility frames makes his most dangerous attacks very manageable. Eventually he will be defeated, and although you receive nothing in the original version, the Final Mix edition at least grants the One-Winged Angel Keyblade, the only one with a massive +16 critical damage bonus.
- Except in the original Japanese version, as this bossfight was added in the international release.