We've seen people make static maps, sure, but this is something else entirely. This is an attempt to bring the entire game of Ocarina of Time from the 3D world of the N64 to the 2D world of the SNES (or, well, the PC).
Hyrule Warriors won't be the only Wii U game where Demon Lord Ghirahim will make an appearance. Masahiro Sakurai revealed Skyward Sword's antagonist as an assist trophy in Super Smash Bros. Wii U. Skull Kid, Midna and now Ghirahim... that's a lot of assist trophies from Zelda games.
French artist Kévin creates his animations in a rather unique way: by using Flipnote Studio, a downloadable application for the Nintendo DS. This makes all of his art look like something from a '90s handheld game.