With Marvel's The Wolverine hitting theaters July 26th, we're getting another long-awaited dose of one of the more famous and anti-heroic superheroes. There's a lot we know about the one we call Wolverine, but seeing as how the comic book character is almost 40 years old, there's a lot we don't know, too. Here are seven things you may not have known about that guy with the lamb chops and claws.

7. He First Appeared in a Hulk Comic

Specifically, the Incredible Hulk #180, then continuing on in #181, and ending in #181. He’s fairly nondescript in his debut, as I’m sure the writers were still crafting his back story, but they got the broad strokes right: He was an angry guy with claws named Wolverine.

6. By His Second Appearance, He Was Already an X-Man

About his debut being nondescript… it’s pretty clear that he was going to be a member of the X-Men from the get-go, and it’s in Giant Size X-Men #1 that we see his sweet hairdo for the first time, as he always had his mask on before that. Granted, he wasn't one of the ORIGINAL X-Men, but the comic book guys got him there as fast as they could.

5. Wolverine Was Supposedly Intended Be Born As a Wolverine Cub

His first origin story was supposed to be as a wolverine cub who gets mutated over time by a geneticist to become human(ish). Len Wein, Wolverine’s creator, vehemently denies this, but the “fact” has been such a part of Marvel lore that it was even included in a X-Men Origins: Wolverine Blu-Ray feature, which just pissed Wein off more.

4. Speaking of Len Wein, Wolverine Wasn’t Created by Stan Lee

It’s easy to assume that Wolverine, because he’s popular and a Marvel character, was created by Stan Lee, the famous creator of many iconic characters, like the Hulk, Fantastic Four, and Spider-Man. Nope. In fact, one could argue that the character wasn't even created by Len Wein, as he was working under direct orders from Marvel editor Roy Thomas, who wanted Wein to create a character that was small, angry, and Canadian(!).

Wein did as he was told, and Wolverine was born.

3. Wolverine Fought for Canada in WWI, and with Captain America in WWII, Then Again with Canada at D-Day, Then Worked for the CIA.

For someone who hates authority, Wolverine sure did spend a lot of time fighting in the military. He arrived at D-Day via parachute. Also, he seems kind of violent for a Canadian, but that’s neither here nor there. He would have been a nice guy to have on your side, though I’m not sure that retractable melee weapons would really be an asset in the age of drones and smart bombs.

2. There’s Only One Way to Kill Wolverine

Because his body regenerates so quickly and efficiently, you’re gonna have to take his head clean off in order to end him. Not only that, but in a profile written by the famous Professor Xavier, it’s said that if you want him to STAY dead, you also better remove his noggin from anywhere near his body and keep it away.

Even for a comic book character, this guy sounds pretty tough.

1. There’s Only One Substance on Earth That Wolverine’s Claws Can’t Destroy

It’s not diamonds. Nor is it balsa wood (Really? That’s your guess? BALSA WOOD?). Rather, it’s Captain America’s shield (Stop laughing. For real. It’s the shield.). Cap’n’s shield is made out of an iron-vibranium alloy, which, for those of you not up on your fictitious metallurgy, is a very, very, very strong metal.

So the best advice to those who are planning on pissing off Wolverine: Don’t. And if you have: Run.