Minor Arcana

You might think that the Major Arcana would be more powerful than the Minor Arcana. But not so. For some reason, in Persona 2 the little cards are the upgraded versions of the big cards. Whenever a persona gains the "modification ability" in a mutation, you can take it back to the Velvet Room and have Igor transform it into a completely new card. Through mutation, you can use personae of a higher level than you otherwise have access to. However, the mutated persona loses all its previous ranks and spells, beginning again at Rank 1.

Which Minor Arcana a persona becomes is determined by level as follows:

Persona level: Mutates into: Candidates for modification:
12 or less Matsuo-sama Level 12 Cup Airget Lam, Harpie, Kimnara, Pixie, Poltergeist,
Robin Goodfellow, Ryume
13-16 Hotei Level 16 Rod Arianrhod, Genjo, Minotaur, Nekomata, Surya,
17-20 Fukurokuju Level 20 Pentacle Fjalar, Jack Frost, Pairika, Phaleg, Shax

21-24 Kanshou Level 24 Sword Aizen Myouou, Hel, Ghandarva, Kabandha, Kanaloa, Kinich Kakmo, Otohime, Tenhou Gensui
25-28 Nankyoku Roujin Level 28 Rod Gullinbursti, Jack O'Lantern, Nemesis, Marduk,
Mars, Taranis, Taishan Niang Niang
29-32 Yebisu Level 32 Pentacle Cuelebre, Kenren Taishou, Melchisedec

33-36 Galahad Level 36 Cup Agrippa, Byakko, Heimdall, Loki, Xi-Wang-Mu,
Seiten Taisei, Sif
37-40 Peri Level 40 Pentacle Baal, Genbu, Heinir, Stymphalides, Surt, Yama

41-44 Nodens Level 44 Rod Aeshma, Ankou, Barbatos, Gundari Myouou, Parvati, Susano-o, Takshaka, Vivian
45-48 Cu Chulainn Level 48 Sword Armati, Charon, Hunab Ku, Hurakan, Rinok, Succubus
49-52 Bacchus Level 52 Cup Abe no Seimei, Ares, Indra, Seker, Skanda, Tsukuyomi,
53-56  Arthur Level 56 Sword Hathor, Kinich Ahau, Mananan, Mithra, Mucalinda, Phoenix, Vritra
57-60 Quetzalcoatl Level 60 Rod Adramelech, Maha Kala, Seiryu, Valkyrie

61-64 Sarasvati Level 64 Pentacle Beelzebub, Isis, Ourobouros, Scathach

65-68 Dagda Level 68 Cup Hanuman, Seth, Varuna, Wong Long

69-71 Futso no Mitama Level 72 Sword Amurdad, Fereydun, Tishtoriya

72 or more
cannot mutate

There are exceptions. None of the characters' inherent personae can gain the modification ability except for Maia (who turns into Maia Custom). Personae who are summoned with material cards, personae who are themselves the product of a mutation, and Fool-type personae are also unable to gain the modification ability.

All characters have at least good compatibility with all Minor Arcana. Best compatibility is as follows:

Level-up Bonus
Best Compatibility
VIT +1
All male characters
STR +1
Katsuya, Tatsuya, Nate, Ulala
TEC +1
Maya, Ellen, Baofu
LUC +1
All female characters