With release just hours away, Marvel Tokon is rushing out the last few character guides, with back to back releases for Deadpool and Carnage. Which leads to a neat little coincidence of grouping characters with very similar color schemes (black, red, and white).
Unless I'm mistaken, he's the second youngest character on the roster after Peni Parker, first appearing in 1991, and it makes sense. Deadpool is a distinctly modern character, with his awareness of greater pop culture and his own existence as a comic book character being a core part of his personality.
The constant references and 4th wall breaks were not as common when the character was conceived, so the fresh concept led to him becoming quite popular, eventually scoring him roles in movies and video game adaptations, including a spot on Marvel vs. Capcom 3 roster.
In that game he was an incredibly potent keepaway character with a fairly unique teleport option, so let's see what he's like in this new iteration.
While some of his MvC moves are back in Tokon, Deadpool here has a totally different identity. Instead of wild mobility through teleports and great keepaway, he's an incredibly versatile hybrid character that has a unique gimmick of self-damage, with a potential to both add or deplete his recoverable health.
For example, one of his moves allows Deadpool to stab himself to damage the opponent or block projectiles. In the process he not only damages himself, but increases his recoverable health. After that, you get access to a special group of "fouth wall break" specials that change M version of his existing specials to new attacks that typically reference something else, from Mortal Kombat to Garou.
While Trigger Happy makes a comeback in a simplified form, he also gets a new and fairly unique grenade attack. You can perform a special to pull out one of 3 grenades (and once you pull 1 type, it won't reappear until all 3 types have been used), which he then holds. While holding the grenade, it can augment his "4th Wall" specials, like EWGF and Falcon punch getting their electric and fire properties respectively. Holding onto them for too long will damage Deadpool, so you have to throw it out, but even then it's not that simple. Deadpool will either throw the name himself, or Headpool will grab it with his mouth and fly to the opponent, after which you can play hot potate like with Faust's bombs.
When it comes to grenade types, things are more simple. Explosive just explodes and does damage, fire grenade creates a patch of fire on the ground that deals DoT, and shock grenade stuns opponents.
Even when it comes to his super moves, Deadpool gets a choice between different variations that all have unique inputs and attacks. Even though ASW rates his ease of use as 3/5, it seems like this will be a rather technical iteration of the character that will demand some mastery before you can unlock his full potential, especially when it comes to combo routing.