Thing

The Thing (real name Benjamin Grimm) is a super-hero with rock-like skin and a member of the Fantastic Four.

The Avengers: Earth's Mightiest Heroes
The Thing first appears along with Human Torch to help the Avengers fight ice monsters when Malekith the Accursed creates a dangerous winter in New York. He returns alongside the rest of the Fantastic Four in the episode "The Private War of Doctor Doom". He and Hulk have a somewhat childish rivalry because Thing never beat him in a fight. He joins the New Avengers in the episode of the same name after the regular Avengers are trapped by Kang the Conqueror. Thing and the Fantastic Four assist the Avengers while battling Galactus and his heralds in the season 2 finale "Avengers Assemble".

Ultimate Spider-Man
Thing was seen from Spider-Man's imagination about his early encounter with Trapster who stuck the web-head with him.

When Spider-Man, mind-switched into Hulk's body by Mesmero, ends up in town, he is attacked by Thing, who was summoned by Nick Fury to try and contain the Hulk. Spider-Man, Hulk (who is in Spider-Man's body) and Thing eventually clear things up, corner Mesmero and force him to switch Spider-Man and Hulk's minds back.

Hulk and the Agents of S.M.A.S.H.
Thing appears attending a card game with Spider-Man, Hulk, Red Hulk and She-Hulk. It is during this time he was suddenly captured by the Collector along with Red Hulk and She-Hulk. He was later freed and sent back to Earth.