History
Colin Thirty-Three was an A.I.M. agent working on the Quintronic Man project, an exoskeleton which needed 5 men to operate, including himself. One of the key agents on the project left A.I.M. before it was finished.
Thirty-Three sent two agents to kidnap professor Burke. In a apparently failed attempt to prevent A.I.M. mission from success, S.H.I.E.L.D. managed to change a face-covered professor Burke with Bruce Banner, who as soon as he entered A.I.M.'s facility, started causing havoc.
Colin decided that the project could've been finished without Burke, and used another A.I.M. agent to cover Burke's place. Other S.H.I.E.L.D. agents who supported Hulk were defenseless until the hero crashed on the scene.
The Quintronic Man then tried to kill Hulk using the lava of the volcano the A.I.M. base was in, but he survived and crashed the suit's protection, allowing the lava to reach Thirty-Three and kill him as well as the rest of the four pilots.[1]