Summons that need to make a comeback.

[Wolf Kanno]

Kanno, what is that bird and snake? We all don't remember the old obscure summons.

Tritoch/Valigarmanda is the feathered serpent.

Terrato/Midgard Zolomn is the snake

Also, while he has actually shown up a couple of times since his debut. I feel like Diablos should stay on as a regular Gravity summon.

No, that should be Atomos.

Nope, Diabolos is way cooler than Atmos.

Ifrit has been MIA since 12.
Last known whereabouts... 10.

He's also in XI and I believe he makes a cameo in XIII in the Nautilus stage show telling the backstory of Cocoon and the war with Pulse. Ifrit doesn't have it nearly as bad as Ramuh.