Just went for 100% and am road-blocked by a legit bug. This isn't just a find a tiny corner of the map that you didn't explore issue (which is really dumb since the map itself doesn't lend itself well to seeing unexplored pixels...). Anyway it's in Willow's End where the bottom right heart is. The sequence goes something like, destroy the heart, big rocks fall, you race them down and go into a portal that puts you next to a life pod and a barrier to break and backtrack. Well I somehow didn't beat the rock, survived, and was able to backtrack but I now have no way of getting to this part of the map. Thankfully there were no collectibles there but my save file is permanently stuck at 99% now ):
Can't get where the cursor is hovering over:
Also really random that I had no idea regenerate was an ability until I realized I was missing an ability and didn't have that achievement unlock yet. Disappointing that is such an easy one to miss that would have been immensely helpful lol.