Wasn't Blue Diamond a sort-of regularly appearing guy in the Dazzler series(hey that was back in the 20th century!)?

Big Guy made a guest appearance in Martha Washington in Space iirc.

Stanley's Monster is a favourite.

i dont' know if they would actually count as an "obscure" charactor, but how about most underutilized, thereby marginalized, charactor:

marvel: rage.

dc: the creeper

rage should be a mainstay charactor ala luke cage, the creeper should be a comic relief/special abilities charactor ala the beast when he was in the avengers.

The Shroud was offered membership in the West Coast Avengers after he broke into their compound in the West Coast Avengers limited series #2.

I love me some Shroud. What a cool character.

As far as my favorite obscure comics character: just look at my sig.

Man, I loved Stanley and his Monster when I was younger; now I try to re-read their stories after Kevin Smith used them over in "Green Arrow" and the tales just aren't the same.

(Don't get me wrong - kudos to Kevin for making Stanley and his Monster "part" of the DCU and all but, I dunno...maybe if it had been done by Neil Gaiman over in "Sandman" it would have worked better).

i would say the question but he's not so obsure anymore

Flash Gordon, Ming the Merciless, Dale, Dr. Zarkov, Aura, Barin w/Forestmen, Thun (now you're getting obscure) w/Lion Men, Vultan w/Hawkmen (in your face Hawkman/Hawkgirl, here are the REAL Hawkpeople), Queen Azura w/Blue Magic Men, Tuskmen etc

<--- 2nded

Big Guy and Rusty the Boy Robot (only 2 issues ever made) <-- and a shortlived cartoon

Let me add john carter and cast

What about the Phantom? Or the Shadow? Or Mandrake the Magician? There's some moldy oldies who could use some Clixin'! I guess it would be a copyrights mess for all that stuff. Who's got the rights to the Shadow or the Phantom right now? Anybody know?

I just loved that guy. When Charles Middleton played him, he reminded me of my father.

Really tho, he set the pace a long time back for meglomaniacs.

hmm, hard to pick one for DC comics, but Marvel's fave obscure char, not seen since the Silver Surfer, was "Midnight Sun", formerly known as "Midnight". Former bad guy, killed by his "brother" Shang Chi, the Master Of Kung Fu. He was then brought back to life, kinda, but the Kree to fight the Surfer. As the Surfer thrives in light, the Midnight Sun thrived in dark. Tho, Midnight was no where near as powerful as the Surfer.
He was last seen being taken in by the Inhuman's, with few of his memories intact and still unable to speak. Also, frighteningly deformed, tho they never showed his face, he saw it and was aghast... as was the Surfer when he saw it.

So, yes, Midnight Sun is my fave Marvel obscure char.