That’s sweet of you, but I’ll be alright 
I used 1 of each troop. I purchased Tier 7 seven times (+49 to all stats) and had level 15 faction pet (I cleared it with pure faction at 300 and then completed it with no losses at 500 non-faction).
It was pretty easy. Just keep pumping up Bile Blackheart and skull kill everyone. Sometimes you even get lucky and lethal kill via ability.