If your opponent has a King, you can target a sub and all drillers on board (and jester) will be destroyed (travels at x2). not sure if it should kill any specialists on board (probably OP) or return them to original base..
while at a base, the jester will nullify the kings advantage of destroying drillers before combat begins.
Sort of a cross between and DA and pirate, but can only be used against a player with a king.
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Damn. If only this game would be supported by the devs and specialists could be added or removed for for a period/permenantly to keep the meta fresh.