If I can only play one IP for the rest of my life, Id want to have the most possible games to choose from, and games that offer some variety. Im assuming that the spin-offs from Mario wouldnt count (Mario Kart, Mario Party, Mario Tennis, Mario Golf, etc), but if they do, all the better.
But all of the other IPs are a lot more limited. Even something like Zelda, for as great as it is, has similar games. The formula is usually fairly standard - great, but standard. There are at least some differences amongst the selection of Mario games, and there are more of them than any other Nintendo IP.
Thats my rationale, for what its worth.
Pretty much this. Mario covers pretty much every genre, which no other Nintendo IP (or IP from any other company, for that matter) can claim. I'd miss the others because they're good, but I'd need the variety.
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