Part of the fun...

Of mutants, is seeing just what the mutant can do. It is frustrating when a mutant is depicted with no clear idea of the mutant's power.

Shinobi Shaw's version of the Hellfire Club had a full inner circle and yet it was never really stated or shown what each member could do.

Idie. Could someone tell me what her actual power is. I just remember she killed a group of people somehow and recently saw her weild fire and ice, I think.

Tessa was fun back in the day because she was simply described as a human computer before being relegated to an average telepath with cybernetic like information skills.

Maybe I am just missing one panel of explanation here and there, but are there any other characters who have undefined powers?

Idie controls/ manipulates temperature

Idie (Oya) essential powers as Pyrokinesis and Cyrokinesis (Control over Fire and Ice).

Tessa (Sage) has always been a Telepath since day one. Her additional powers are that she's got a 'computer' brain which is how she processes and stores information super fast. She's not a Cyberpath, although her usual equipment (Her tech-glasses) when combined with her Super-computer brain emulate the idea as she's just so darn good at hacking. Moreover, she can read and alter a person's DNA, (Kinda like biokinesis I guess) often using it to 'jumpstart' a Mutation as she did with Lifeguard.

@backflip: Moreover, she can read and alter a person's DNA, (Kinda like biokinesis I guess) often using it to 'jumpstart' a Mutation as she did with Lifeguard.

Rachel was able to alter her dna but it was said that she was able to do it using her tk, does that mean she has biokinesis too?

@darthphoenix: No because Rachel is just manipulating matter I guess? Whereas Sage's power basically is 'evolving' people in the simplest of terms.

@backflip: actually Tessa was not revealed to be a telepath until the 90s, post Upstarts when Sebastion Shaw was thought dead and Emma was in a coma. In a story with Shinobi going head to head with a rival Hellfire King, Tessa uses her telepathy to force the X-men involvement. Jean and Psylocke were surprised Tessa was a telepath and gave her some mental payback.

Prior to that, Tessa provided data and stats on request and volunteered observations, but it was not specifically stated she was a telepath. Or recognized as such by Emma, Xavier, Shaw or anyone through dialogue.

@sinisteri: Well a convenient explanation for that would be the 'firewall' ability that she has which grants immunity to telepathic interference but equally disables her own psychic powers.

I think there was a story point as to why she did not use her telepathy for a period of time to explain why she was not always known as a telepath. That was a retroactive explanation. Claremont never said she was a telepath and purposely gave her an air of mystery.