Looking back, the deathmatch idea might really bruise some egos, maybe lead to an all out brawl for real (depending upon the temperments of the youngsters involved). But it would make quite a bit of theater otherwise! (assuming a TPK didn't force them to start over completely when playing solo)
Actually if the stakes were only bragging rights (or "you get to keep the other party's gold") it could be a regular thing. Like the grudge match every few fights in some of those old arcade brawlers (Street Smart, Pit Fighter). You go up against Zargon and play some quests every so often but then the challenge is accepted and you try to win the gold from the other team. I dunno, maybe it's too high stakes to maintain good relations...
As for the Champion thing, I love the idea of the 500 reward for completing quests. I made it in my houserules (added to the NA base) as "3-5 quests" at Zargon's discretion. So if they were particularly easy ones, here I'm assuming we are not necessarily playing from 1 to 14 in order, but freely picking from all available quests from session to session... then 3, if they're harder ones then 5. And I added a new rank after that called "Knight" which would be equivalent to the normal "Champion" you become after beating the WitchLord (so 10-14 quests total completed).
I wouldn't give them an extra gold reward at the completion of Knight but I would upgrade various things at Champion and at Knight. This makes the game easier, but I was thinking something to give them a sense of advancement AND a way to make it more tolerable to play the insane difficulty of the EQP/BQP without having to artificially nerf those packs as-is. To compensate, I would give increasing odds that new Monsters on the board would be extra powerful (rather than adding extra monsters or messing with the stats of existing ones).
I know many others have gone with their own version of advancement, leveling up, etc. (the Japanese game system let you gamble to level up your body points between quests even) but here's my system, I tried to keep it fairly simple, but it does involve use of colored dice, Combat Cards, and an extra chart or two.
Also, that little "Champion" symbol from the Adventure Design Kit is cool to slap onto your character sheet. I guess for the Knight it could add crossed swords or spurs or something.
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