I prefer the 2D games, as the old formula seems to work best in those. The better 3D games (MM and TWW) needed to radiacally change the formula to help them stay good, OoT felt way too much like another ALttP (but more tedious) and while TP felt somewhat "fresher" compared to OoT, the Wolf transformation didn't really impress me and the only good characters were Midna and Zant (also Ilia and Colin, but to a lesser extent).

And IMO, the Zelda series had lost it's "purity" after the Four Sword games, they were not too bad, but they just felt...tacked on...

The Metroid series also had a way better transition to 3D (with the exception of Hunters).

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"Let all that once was fade into oblivion. I welcome the end of existence."