That Cracked article doesn't include any quotes or sources, and some of the Comments at the end of the article question its accuracy:
Love you guys but #2 couldn't be more wrong. Byrne started drawing the X-Men in 1977 (brillantly I might add) that part is true, but the Thunderbird character was splattered all over the side of NORAD mountain in 1975. John was drawing Iron Fist and some other lower level titles in 1975.And:
Wait a second, the issue where Thunderbird died was created by Len Wein and David Cockrum (and was scripted by Chris Claremont), this happened YEARS before Byrne joined the book.
Here is a link to an interview with Cockrum about Thunderbird:http://goodcomics.comicbookresources.com/2005/10/13/comic-book-urban-legends-rev...Here is Peter Sanderson discussing the topic with Dave Cockrum, from The X-Men Companion – Part I:
SANDERSON: “Now was it originally intended that Thunderbird would really be a member of the team? When was it decided to kill him off?”
COCKRUM: “Kind of at the last minute. The way this all came about was that when we were first planning out that first issue, we decided what we were going to do was have it be an aptitude test or an entrance exam or something like that. They would be sent off to rescue the original X-Men, but the original X-Men would not actually be in any danger. We figured if it’s an entrance exam, theoretically, there are people who are going to flunk as well as people who pass, and so we had Banshee and Sunfire, and we were going to flunk ‘em. Then we thought, well, that doesn’t seem fair, we ought to have a new guy to flunk too, a new guy who’s unsuitable. So that was what Thunderbird was for, to be a flunker. He was unsuitable because he was anti-social. Hah! As if Wolverine’s not anti-social. But at the last minute- well, I liked Banshee and we all liked Thunderbird, so we figured to hell with it. It turned out not to be a test anyway. So we had Sunfire, who nobody much liked, go off in a huff, and we kept Banshee and we kept Thunderbird. But then we didn’t know what to do with Thunderbird because we never thought him out. It was easier to kill him off than to think him out.”
SANDERSON: “Was it thought that he duplicated Wolverine too much?”
COCKRUM: “He duplicated both Wolverine…”
SANDERSON: “And Colossus, with his super-strength.”
COCKRUM: “Almost everybody in the group did something he did, and he seemed kind of superflous. He was fast, he was strong. I mean, he was fast enough and strong enough to run down a buffalo and pull it down, and faster than Colossus, but not as strong. The whole thing seemed pointless so we did him in.”
SANDERSON: “Do you think that it was a good idea to do him in so early? I know that when the story was written, you thought that it was only going to be a quarterly book, but nevertheless, it was only the second story. Len [Wein] says it was done for shock value.”
COCKRUM: “I guess it was more than anything else. We couldn’t figure out what to do with him, so we figured, all right, let’s kill him off. You don’t often find a character that’s introduced and so abruptly killed off. I imagine it did shock a lot of people. We never intended to bring him back, although we’ve toyed with the idea of having a younger brother show up wearing the same costume.”
Here is another link with citations and quotes from Len Wein and Dave Cockrum:http://gentlemenofleisure1.blogspot.com/2011/02/x-amining-x-men-95.htmlLen Wein on the death of Thunderbird
"'He was created to die...We did that intentionally to let the readers know, 'Anything can happen. Nothing is set in stone.'" Asked if there were concerns about potential backlash over a minority character being the target of such a move, he replied, 'Never crossed my mind.'"
Lamken, Brian Saner. "The Phoenix Effect: 25 Years of the All New Uncanny X-Men." Comicology Fall 2000: 28-29.
Dave Cockrum on the death of Thunderbird
"Cockrum remembered things slightly differently...He and Wein initially planned the new team's first mission as 'an aptitude test or an entrance exam or something like that...They would be sent off to rescue the original X-Men, but the original X-Men would not actually be in any danger. We figured if it's an entrance exam, theoretically, there are people who are going to flunk as well as people who would pass.' Banshee and Sunfire, the previously established characters, were going to flunk, said Cockrum. 'Then we thought, well, that doesn't seem fair; we ought to have a new guy to flunk too, a new guy who's unsuitable." That new guy was Thunderbird, and when plans changed he made the unenviable career move from failure to corpse."
Lamken, Brian Saner. "The Phoenix Effect: 25 Years of the All New Uncanny X-Men." Comicology Fall 2000: 29.
"Thunderbird was made up pretty much on the spot. I just wanted to do a Native American character. I was tired of buckskin so I gave him this flashy costume. Marvel rejected my first costume. Len said he looked too much like Steve Canyon, the character Milton Caniff created in the 1940s. I'm sorry we killed Thunderbird off because I thought he was a great character.
Thing was, he came in as an obnoxious wise-ass and loudmouth and Wolverine did that better. We decided we didn't need two loudmouths, and rather than develop his character, we decided to kill him off for shock value. It was the first time anyone had ever killed off a character and not said anything about it on the cover."
DeFalco, Tom. Comic Creators on X-Men. London: Titan Books, 2006. p86