Dueling Games: Sonic Rush Adventure with The Legend of Zelda: Phantom Hourglass. Released within several weeks of each other, both games involve their respective protagonists getting caught in a storm that washes them ashore in a land they've never seen before with their equipment destroyed or lost. Both games have a ship-building feature and paths across the oceans drawn using the DS's touch screen. The games have incredibly similar color schemes and an annoying new character who cannot pipe down but is good with nautical vehicles. As if that wasn't enough, both games have a haunted ship with a green tinge for their fourth stage.
Franchise Killer: Rush Adventure was received well, but it sold poorly compared to other 2D Sonics, putting the handheld branch of platformers on an indefinite hold. Since then, Dimps has been relegated to making handheld adaptations of console games rather than original ones.