Surprise! 3-vs-3 sports spin-off Metroid Prime: Blast Ball is available to download now on Nintendo 3DS for free, Nintendo has announced.

The free game sees two teams of players piloting mechs around an arena, scoring goals by firing their blaster at a gigantic ball. Eurogamer likens it to "Rocket League with a little Mario Kart and a side-order of mechs", which sounds all right to me.

Both local and online multiplayer is supported, and there's also a single-player option for players who'd prefer to go it alone.

Blast Ball's release comes ahead of this Metroid Prime: Federation Force, a premium co-op-focused game due to launch on Nintendo 3DS this September.

Source: Nintendo

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