I was able to get some of the lower levels. I used a level 7 Plantlers and won most of the time.
Level 17
Armordillo
Rock fire
Lv. 3
Use rock
Level 18
Rock Rhino
Rock
Lv. 5
Use nature
Level 19
Solar simian
Nature Fire
Level 4
Use rock
Level 20
Rampage
Rock Fire
Lv.
Use rock
Level 21
Fairy Ferret
Nature Fire
Lv.
Use rock
Level 22
Pyro Pony
Fire
Level 10
Use rock
Level 23
Bamboos
Rock Fire
Level 6
Use nature