His abilities are Skill Based, because failed to gain abilities from Terrigen mist (or such) like other Inhumans did (aka Bolt, Medusa,). So they made him sort of a Combo Class (just for Cats required to upgrade).
They seemed to be experimenting with requiring a mix of catalysts for champs who kind of ride the line between classes from a lore perspective. Think Unstoppable Colossus (Mystic and Mutant) or Quake (Science and Cosmic). They tried it with Karnak and decided they didn't like it. To date, he's still the only champ who requires 2 different classes of catalysts to rank up.
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Ya this is same with 3*, I didn't know this is for real and not a bug.