Square Enix have announced the Japanese XBLA release of Crystal Defenders and cult favourite Yosumin, signalling the first move in their plans to bombard Xbox 360’s download service with original content and ports.

The first volley in this assault comes in the form of Crystal Defenders, a Final Fantasy Tactics meets Tower Defence strategy game, also being released via Japanese PSN and Wiiware. This will be followed up by Yosumin Live, a port of simple yet deadly-addictive DS puzzler Yosumin that adds online multiplayer and leaderboards to the single player experience.

Translated by 1UP from a Japanese press release, Square Enix revealed that the project will not just offer ports of old games, but new titles also. “Beginning with these two games, Square Enix plans to release a steady stream of its popular titles - as well as original content - on Xbox Live Arcade.”

But it’s the old games that have got everyone excited. 1UP are suggesting the possibility of the recently remade SaGa 1, whilst Kombo have got themselves all worked up about a XBLA release of Final Fantasy IV: The After following the discovery of a “mystery link” (Oooooh!) on the Japanese Microsoft website that has “finalfantasy4″ in the url. Exciting!

Of course, this is all Japan-only right now but worldwide XBLA releases can’t be too far behind right? Keep your fingers crossed people!