Double Cut after Climhazzard can be mashed and is a true combo everytime if you don't mash it prematurely. Wait out a little bit, you will notice when you start pressing buttons and nothing happens after the second hit of Climhazzard.
Double Cut -> Cross-Slash requires the opponent to be close to the ground, but in a mid-air state. Again, you can start mashing Cross-Slash after the first of Double Cut but obviously a precise input is always better in the long run. The whole combo relies on landing lag anyway which is a juicy 13 frames.