Fire challenge

What is the best stage for the fire challenge? Can’t find anything good.

You should find it all here and more.

Province 4 level 1 is the best redmonster/world energy but still suck, red chest are most problematic to open (maybe only for me)

20-4 had the best results.

20-4 need 7(or 6) energy world for 11? monsters.
4-1 need 3 energy for 2(very rare) to 7-8 monsters
It can give the same number of monsters/energyworld but I prefer 4-1

thanks for all the repies