The 3 most important ones are
jump...airdash back jb right before you land - unblockable
long airdash....ja land 2a
empty jump 2a - Only works after you hit unblockable 10000x
If they blocked any of those and they're a half moon character with >100 meter it's best to time a 214b so it hits right after the last cactus punch so they can't get out with bunker.
Fancy stuff
IAD j[c] x 3 land 236[a] gives perfect timing for last hit of cactus to wallbounce after overhead hits so you can combo off of it. For low, do 236{a} 2a
round ender - high jc with cactus' last punch double jump jc fuzzy.