Final Fantasy screenshot

Final Fantasy X - Dark Aeons

Aeons are the opposite here and they don't come nice, so train up (a lot) as they can have nasty attacks. Just remember, when an Aeon has his Overdrive full, summon a weak aeon so that their attacks won't damage your party members as the game could be over. And try not to use cheats.

Dark Valefor

HP: 800,000
AP: 10,000 (normal) 15,000 (overkill)
Items: Dark Matter x2
Steal: X-Potion x4
Attacks:
Energy Ray - Deals 10,000+ damage on all characters
Energy Blast - 52,000 HP+ damage on all characters
Physical Attack - 3,500 HP+ damage on 1 character

Location: A summoner shall stand at the Entrance of Besaid Village and block your way, The summoner will Summon Dark Valefor...

Tip: Dark Valefor is easy when compared to the other Dark Aeons. If your stats are high (especially defense), his attacks won't do a lot of damage but you have to pay attention to his overdrive. To survive Energy Blast, cast Auto-life on your party.

Dark Ifrit

HP: 1,400,000
AP: 20,000 (normal) 30,000 (overkill)
Items: Dark Matter x2
Steal: Mega Phoenix x2
Attacks:
Meteorstrike - Deals 20,000+ damage on 1 target.
Hellfire - 33,000 HP + damage against all targets.
Physical Attacks - Deals 9000 HP + damage on 1 character.
Elemental Immunities: Absorbs fire, immune against lightning & water, half damage against ice

Location: Entrance to Al Bhed Home, a man will ask you to help him find his daughter. You must choose yes and he'll ask you to look by the cliff. You'll see Dark Ifrit there.

Tip: Dark Ifrit is stronger than Dark Valefor but he should still be easy if you have high stats. Ice attacks are useless against him since their damage is halved. To survive Hellfire, make sure your party has Auto-life on your party just before Ifrit uses his overdrive.

Dark Ixion

HP: 1,200,000
AP:
1st Battle - 20,000 (normal) 30,000 (overkill)
2nd Battle - 40,000 (normal) 50,000 (overkill)
Items: Dark Matter x4
Steal: Stamina Tablet x2
Attacks:
1st Battle:
Thundaja - 4000+ damage on 1 character.
Aerospark - 6000+ damage 1 character.
Physical Attacks - Causes Sleep.
2nd Battle:
Aerospark - Instant kill (99,999 damage) on 1 character.
Thor's Hammer - 19,000+ damage on all characters.
Physical Attacks - Causes Sleep & Full Break.
Elemental Immunities: Absorbs lightning, immune against ice & fire, half damage against water.

Location: Talk to the soldier under the lightning rod tower, north of the agency. Once you do, he'll run off and call a summoner who will then summon Dark Ixion.

Tip: Dark Ixion has to be defeated twice. On your first encounter you should have no problems as long as you dispel Full Break from your characters. If you have a very high evasion, you should be able to dodge his counter attacks. On your second encounter, Dark Ixion will be harder to beat. If you get affected by poison or berserk, dispel them immediately. Use Auto-life to survive Thor's Hammer.

Dark Shiva

HP: 1,100,000
AP: 20,000 (normal) 30,000 (overkill)
Items: Dark Matter x2
Steal: Mana Tablet x4
Attacks:
Physical Attacks - 4000+ damage to a character.
Heavenly Strike - causes KO / death
Diamond Dust - 84,000+ damage! on all characters.
Elemental Immunities: Absorbs ice, immune against water & lightning, half damage against fire.

Location: Macalania Temple Entrance. A Guado Guard will block your path and summon Dark Shiva.

Tip: Dark Shiva is quite fast so you need to have a very high agility. Since Diamond Dust deals more than 84,000 damage make sure you have Auto-life on your party just before Dark Shiva uses her overdrive.

Dark Bahamut:

HP: 4,000,000
AP: 30,000 (normal) 40,000 (overkill)
Items: Dark Matter
Steal: Twin Stars x2
Attacks:
Physical Attacks - 12,000-13,000 damage on 1 character.
Impulse - 6,000+ damage in addition to Slow, Full Break & Petrify on all characters.
Mega Flare - Massive damage to all characters, that is if you're not inflicted with Full Break,
Elemental Immunities: Half damage against all elements including Holy

Location: Where Yunalesca stood and died, Zanarkand Dome

Tip: Dark Bahamut is really tough so your stats have to be extremely high. You will also need Ribbon or at least Stoneproof. Dispel Full Break as soon as you get affected by it. Dark Bahamut counters with Impulse every 5/6 turns. Just make sure he doesn't use it just before his gauge fills up, else it will get followed by his overdrive. Use Auto-life to survive Mega Flare.

Dark Yojimbo

HP: 1,600,000
AP: 8,000 (normal) 10,000 (overkill)
Items: Dark Matter x7, Master Sphere x1
Steal: Stamina Tonic x2
Attacks:
Daigoro - 6,000+ damage with Petrify on 1 character
Kozuka - 12,000+ damage with Full Break and Curse on 1 character
Wakizashi - 22,000+ damage on all characters
Zanmato - instant death on all characters
Elemental Immunities: Regular damage against all elements including Holy

Location: Cavern of the Stolen Fayth, step on the teleport panel to get to the back of the cave then try to go back out. A summoner will block your path and call Dark Yojimbo. [Calm Lands]

Tip: To actually defeat Dark Yojimbo, you must kill him five times. For these battles high accuracy won't be enough. You'll also need high luck if you want to land in your attacks. Just like Dark Bahamut, you will need Stoneproof or Ribbon so as to avoid getting petrified. Dispel Full Break if you get affected by it. The only way to survive his overdrive is to summon an aeon and let him/her get hit by Zantetsuken instead of your party. Unfortunately Auto-life won't work in this case.

Dark Anima

HP: 8,000,000
AP: 30,000 (normal) 40,000 (overkill)
Items: Dark Matter x2
Equip: Sanctuary
Steal: Three Stars x2
Attacks:
Physical Attacks - 10,000+ damage with Petrify and Curse on 1 character.
Mega-Graviton - Massive damage (46,000+ at 99,999) with Sleep, Blind, Doom, Silence, Curse on all characters.
Pain - Instant death on 1 character.
Oblivion - Instant death + Osmose on all characters.
Elemental Immunities: absorbs all elements, immune to Ultima and Drain

Location: Mt. Gagazet Gate. Go to Gagazet Mountain Cave and repeat the 1st Trial of Gagazet (Wakka's ball challenge). Once you're done, Anima will be waiting at the gate of Mt. Gagazet.

Tip: Dark Anima is very strong. Ideally, you should have Ribbon to protect yourself from Dark Anima's status ailments. Auto-Phoenix is also useful but don't forget to buy enough Phoenix Downs before the battle. Use Auto-life to survive Oblivion, and remember to restore your MP once your characters are revived.

Dark Mindy, Dark Sandy, Dark Cindy

HP:
Mindy - 2,000,000
Sandy - 2,500,000
Cindy - 3,000,000
AP: 30,000 (normal) 40,000 (overkill)
Items: Dark Matter x4, Master Sphere x1
Steal:
Mindy - Teleport Sphere
Sandy - Friend Sphere
Cindy - Return Sphere
Attacks:
Mindy:
Calamity - Casts Poison, Blind, Curse, Silence, Full Break on 1 character.
Passado - Inflicts Death on 1 character.
Sandy:
Physical Attacks - 12,000+ damage with Petrify on 1 character.
Razzia - Instant death on 1 character (99,999 damage).
Cindy:
Camisade - Instant death on 1 character (99,999 damage) plus Osmose.
All of them • Delta Attack - Instant Game Over
Elemental Immunities: Regular damage against all elements including Holy

Location: From the North End of Mi'ihen Highroad, go north to Mushroom Rock. You'll see 2 summoners there, approach them.

Tip: If you run from them you'll be able to defeat them one by one, and you'll have the advantage of not getting attacked by all three of them at once. So I do suggest you take this option, otherwise it is very hard to defeat all 3 of them at once. If you get stuck with the three of them, the Dark Magus Sisters will be able to use their overdrive Delta Attack, which can only be resisted by sacrificing an aeon.

Penance

HP:
Body - 7,000,000
Arms - 600,000 each
AP: 100,000 (normal) 130,000 (overkill)
Items: Dark Matter x3, Master Sphere x3
Steal: Elixir x6
Attacks:
Body:
Obliteration - Deals 22,000+ damage plus Slow on all characters
Right Arm:
Calamity - Casts Poison, Blind, Silence, Curse, Full Break on 1 character.
Mighty Guard - Casts Shell, Protect + Regen.
Physical Attack - Deals 33,000+ damage on 1 character.
Left Arm:
Tetra-Graviton - Massive damage on all characters (74,000+ at 99,999) with status ailments
Physical Attack - Deals 33,000+ damage on 1 character.
Elemental Immunities:
Body - Absorbs all elements including Holy; Half damage against Ultima
Arms - Absorbs all elements including Holy; Half damage against Ultima

Location: Select Airship Destination (You will only be able to have a chance once all the other Dark Aeons are dead)

Tip: To defeat Penance you need high luck, accuracy, attack and defense. The best characters to use are Tidus, Wakka and Rikku equipped with Celestial Weapons and knowing all Overdrives. During battle use skills like Quick Hit and Quick Pockets. When the overdrive gauge is full use your characters' overdrives and try to damage Penance as much as possible. Note that overdrives never miss.

Always kill off the arms first, so that Penance won't be able to use Judgement Day. In the first part of the battle, Penance will use Obliteration. After his HP falls to about four million, part of Penance will fall off and Obliteration will get replaced by Immolation. Remember to dispel Full Break if your characters get affected by it.