Top: as is widely known, the game internationally called Super Mario Bros. 2 is based on a previous

Top: as is widely known, the game internationally called Super Mario Bros. 2 is based on a previous Japan-only game called Yume Kōjō: Doki Doki Panic, but with a number of alterations such as replacing the playable characters with Mario characters. This leads to the fact that nearly every character that is usually thought about as “originating in Super Mario Bros. 2″ (like Birdo, Shy Guy, Snifit, Wart etc.) actually originated in Doki Doki Panic instead. However, there is one exception. The boss of Level 5-3 in Doki Doki Panic is another rematch against Mouser and not an original enemy.

Bottom: in Super Mario Bros. 2, this Mouser was removed and replaced with a boss programmed specifically for this game: Clawgrip. This makes Clawgrip the only character whose first appearance was actually in Super Mario Bros. 2. (Note that some entities changed graphics, such as Mask Gates looking like human masks in Doki Doki Panic and like bird masks in Super Mario Bros. 2, however, only Clawgrip was not a reskin of a previous entity and was programmed in from scratch.)

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