I already known it's impossible to use Lv15s team since Campaign Mode came out, now AI can use no damage moves like ID, II, Regen, etc.
And now we need to face 2 tough creatures with Regen, it's doable in old version, but now we need to cut multiple HP bars on those creatures.
Spinonyx for any, then Erlidom to catch-up
Pterovexus for Para (DoT, Pin or Distraction)
Maxima for Edmonto and Para (as a Guard)
Timer (Rare)
Step 1 6:08
Step 3 8:54
And I summoned Lord Utahraptor (Back off!)
...
https://www.youtube.com/watch?v=yCDLPm8sOWg