Sup frnds. Few days ago I found this characters and bundle.

I think they are great, but I can`t find where they were used and who is an artist. If you know smt tell me and you`ll get bonus in your karma.

Are you talking about the art style, or the characters?

The green squid-faced guy looks like Cthulhu, as a generic figure the creature of evil is potentially available for anyone to use. Arkham House owns many rights to the specific Cthulhu character, but not the concept of squid-face since there are several ancient mythologies that have someone similar. If you want to use the character, check with a lawyer. Depending on use and the mythos you are building, you may or may not need to strike a deal with Arkham House.

The wizard looks styled after the final fantasy black mage, which they have reused and made iconic; I would think carefully before using that graphics style in a game. The blue-cloaked, dark-faced, gold or red trimmed character is within Square-Enix's domain. I would not touch that character in a game due to extreme legal risk.

The red guy may be based on many different game characters, but with a pirate "Jolly Roger" logo eyepatch and peg leg, you could make a similar generic pirate based on redbeard (translated as Barbarossa) who have been real life people over the centuries, including famous pirates, military leaders, and even one who was one of the greatest medieval emperors. A red-dressed, red-bearded pirate is generally available for anyone.