Up to right before the final battle in both Terranigma and Axiom Verge. Unfortunately, even after combing over all of SirTapTap's maps, seems I'm missing 1% item completion (a health power up)... so I dunno what to do. Posted in the NeoGAF thread about it.
Anyways, Axiom Verge is an awesome take on Metroid. It subverts a few of your expectations of the genre, has a lot of world to explore, a decent challenge level where you will die if you're not careful, and gives you lots of cool powerups... not to mention, having that sense of mystery so lacking in modern gaming. Only problems would be - simplistic boss patterns, annoying sound effects, and the occasional twitchy controls.