A mod of Kirby's Adventure that adds new levels and lets the player play as Boxguy the Box.
From Rom Hack Plaza description My character Boxguy the Box gets stuck in Dream land because of the mystery of a man named Top Hat Man! You got to help him get out dreamland by defeating King Dedede and by saving Dreamland, so he can take a nap to get home! (or play Somari or something.)
New Super Mario Land is a recreation of Super Mario Land (Game Boy) using New Super Mario Bros. (Nintendo DS) assets and released for the SNES, with pseudo-3D graphics and a new co-op multiplayer mode.
Platform / Adventure / Action / Fantasy
This is a complete hack of Super Mario World. Don't expect any new graphics here; this game is all about the level design. All the levels and worlds are new, and some of the worlds have themes not present in the original game, such as a water world and an ice world.
Mario's New Earth is a ROM hack/mod of Super Mario 64 created by PixelSM64, with 125 Stars.
Super Mario Odyssey DS is an unofficial fan project, a mod of Super Mario 64 DS that reimagines Super Mario Odyssey for the Nintendo DS.
Sonic 1: South Island Definitive is a hack by RadiantNexus Team, which seeks to reimagine Sonic 1 by rearranging levels. remixing music, adding features from future games, and readding scrapped ideas in new and interesting ways. Major features: 3 acts of reimagined level design, including one act that has yet to be fully reimagined in any other hack. A miniboss. Massive art overhaul all over the place. Music made by ProjectFM and MechaKnuckles. Menus! A custom splash screen. There's been massive engine overhauls as well, including the Sonic 3 level layout format for massive levels, and the Sonic 3 object manager to go alongside this.
Sonic: Christmas Trouble is a festive, high-quality ROM hack of the original Sonic the Hedgehog for the Sega Genesis. First released for the Sonic Hacking Contest 2017, the project is a complete seasonal overhaul that replaces the standard levels with winter-themed environments.