Undertoad is an Alternate Universe created by LucasPucas, and co-created by Starfury and Patwhit01.
This AU combines Undertale with the Super Mario universe. It uses the sprite-comic format that follows a fallen Toad's journey through the Underground, meeting some familiar faces along the way.
Fiery the Flower
- The first character encountered is Fiery the Flower, an evil fire flower who isn't what they seem.
- Kammy Koopa, Bowser's right-hand assistant from Paper Mario and Paper Mario: The Thousand Year Door, watches over the nameless Toad for the RUINS arc.
- Mario is the first character encountered in the Snowdin arc. He is a lot more mellow than his game persona and seems to take more after the incarnation of Mario seen in the likes of the Super Mario Bros Super Show.
- Compared to Luigi, he doesn't care much about capturing Toads.
- He helps you out throughout Snowdin, such as scaring off Jr. Troopa and giving you the Happy Heart badge.
- In part 15, Mario jumps into Toad's menu and fixes it by adding a BADGE option.
- Luigi, Mario's younger brother, is the second character encountered in the Snowdin arc. He dons his Mr. L outfit from Super Paper Mariofor reasons yet unknown.
- He wants to capture a Toad to get into the Royal Guard so he can finally be paid attention to. He is the main obstacle throughout Snowdin, setting up puzzles and schemes, and even attacking with his own Brobot, to capture the Toad. They always backfire.
- Apparently, all of Brobot's buttons are green.
- Daisy, princess of Sarasaland, is head of the Royal Guard. They remain in contact with Luigi. Not much is known because they haven't been encountered yet.
- Peach, princess of the Mushroom Kingdom, now works as a scientist. Not much is known because they haven't been encountered yet.
- Bowser, king of the Koopa Kingdom, is now king of the Underground. Kammy and Bowser have drifted apart for reasons yet unknown.
- Nothing is known about Shruby at this point except that they are the "true name".
- Napstaboo is a shy Boo encountered in the RUINS arc, who just wants to be left alone.
- Donkey Kong owns a banana shop in the RUINS in order to make a profit.
- Parakarry, the mailkoopa partner from Paper Mario, is the first miniboss fought in Snowdin. He is encountered in a dark cave trying to find a lost letter, when he attacks Toad out of fear.
- The Koopa Bros. from Paper Mario are the second minibosses fought in Snowdin. They attack in two stacked formations, but are quickly knocked down by precise snowball throwing.
- Jr. Troopa, the mischievous Koopa kid from Paper Mario, is the third boss fought in Snowdin. He is encountered when he attacks Toad for "stepping on his playground". He runs off when Mario comes to Toad's assistance, offering to "fix [Jr. Troopa] for ya".
- Petey Piranha is the fourth and final miniboss fought in Snowdin. After Toad is launched out of the secret platforming segment, they land in front of a sleeping Petey Piranha, who awakens in a fit of rage and attacks.
- Kooper from Paper Mario runs Sherborough's shop, encountered in Part 15. He sells four different items, but tells Toad that he gradually gets more stock whenever he finds "cool stuff", and offers his phone number.
- The RUINS are now blue, to match the popular color scheme of the Underground levels from Mario games.
- Snowdin Forest is a lot more mountainous, adding in platforming segments.
- Sherborough is Snowdin Forest's only town. It features a shop run by Kooper, a bar run by Podley, and the home of the Mario Bros.
- Luigi's final challenge before going into battle is a gauntlet on the side of a clifface, aptly named Luigi's Challenge Cliff. It is filled with puzzles and action sequences against the previous Snowdin minibosses.
- Jumping is a new mechanic added, for solving puzzles by breaking blocks, or, shown in Part 13, for secret platforming segments.
- Badges are a new mechanic added, similar to how they work in the Paper Mario games. The first badge, Happy Heart, is given to Toad by Mario after the fight with Jr. Troopa. It works the same as it does in its original game.
- It is not yet known who replaces Mettaton, but the creator, LucasPucas, has stated multiple times that the Mettaton replacement is not Waluigi, due to large amounts of people trying to pass off Waluigi being Mettaton as canon.