NervousXtian
Thought Emoji Movie was good. Take that as you will.
The thing is (and I think this is a problem with the game in general) that the dungeons for these captures are so hard that, in order to get them, you already need to have a strong team; Oboro's dungeon, especially, is harder than the rest. It's the same problem with totems. You need them to make your team stronger, but you also need a strong team to get them in the first place. It's not like, say, Hera in PAD, where she's a milestone victory--tough but beatable.
But yes, I "gotta catch 'em all," too.
I think it's meant to make people use gems to continue battles to get more IAP. Just a hunch.
..but yes.. unless you had good luck with the RNG and got some REALLY good pulls with your free gems (and didn't waste a lot of them like I did on slots and continues) you can honestly hit a pretty damn big pay wall.