Soleron on 16 February 2010
It's the only game I've played continuously (a few times per week) since it first came out in 1999. Both times a new game has come out (SSBM and SSBB) I've just switched to playing the new one, intensely for a few weeks unlocking stuff then back to a few times a week.
No other game has managed that for me. Sometimes I've gone 2-3 years without playing a Mario game, much as I love them.
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