Thread:Chikalin/@comment-25130395-20150525064813/@comment-24366645-20150528192250

Yes you're supposed to save up your chips for the rare scratch. That's the best way to get good units! Some event dungeons have good units, like descends. However, some are difficult to clear.

Hmm, well it depends on the dungeon but Q3 in a collab can be between approx. 10-15%. But again, we have no way of confirming this. All you can is try and try again :/