We loved Viva Piņata! But much as we loved Viva Piņata (and as much as we assaulted you with that love day after day for months afterwards), it's no secret it sold pretty badly. Over a million copies is decent going, but not quite the return you want after four years of hard slog. Certainly not if you're Rare, Microsoft's most expensive acquisition since the light - and everything else - went green on the Xbox project. So, we ask, beached on a futon in the bowels of Rare's idyllic countryside lair opposite two of the game's most senior developers, why do a sequel?