How did you get so many royal thorns at this point? max is 4 in dwarven lands, Spider is 2nd battle, so elven lands are not open yet. I haven't seen thorns appearing in human lands, and as a warrior, you don't have a decent sacrifice to create royals from other high-hp level 5 units yet.
Unless Lew Klisan was selling a crapload of royal thorns (which makes this playthrough a snap), I don't see how you could have gotten so many. The school of gloom requires at least 4 arena wins without joining a guild to provide better troops and items.
If Lew is selling royal thorns, then doing the Gloom's task is as easy as it gets. I have never seen the bounty guild to sell royal thorns (just cyclops).
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