In the case of Phantom Leader and many others, it’s a result of the game not being 64-bit, and the dev not updating it (usually due to cost vs. return). I believe Phantom Leader was the work of one guy. I wish the IOS store would recognize if you logged in on an old device and route you to old games that would still run on that device, rather than just delete them out of the store entirely.
I’ve been playing Monster Sanctuary quite a bit this week. It was billed as a Metroidvania (sweet) mixed with a monster catcher (awesome). It lives up to that billing and is pretty good, though it doesn’t really reach the level of being great. It has great 16-bit art and an awesome soundtrack. Monsters all have skill trees that you can put points in to, making the RPG element of the game feel fairly deep. Battles are turn-based and feature plenty of buffs, debuffs, and elemental weaknesses. On the metroidvania end, the game is a 2D sidescrolling platformer with areas that cannot be reached until you find certain abilities (like the quintessential double jump) or capture a monster that gives you certain abilities, like breaking bricks, activating switches, etc.
It has been a fun diversion and I’ll be lying if I said it didn’t get me hooked. I think I bought if for $3 on my PS5, which is a steal.