Medallion of Vengeance

[LDiCesare]

1vs1 works fine to do tests. You can also add items and commanders in the .map (add 2 lines: #commander 333 #add_item "medallion of vengeance") but the drawback of this method is you won't realise the actual cost of the items (spending mage turns etc.).
I once played a battle where I had setup several black lords with medallions of vengeance to attack a lot of Ermor chaff. The explosions were quite efficient. Longdead horsemen, regular longdead, skeletons, etc. burnt quite well.