I'm working on a game design for a pseudo-deckbuilder inspired by Friedemann's game "Friday" and the video game Recettear, in which players are shopkeepers selling items to adventurers... the adventurers are represented by the decks, and as such are not owned by any player but rather are shared. The players then "hire" those adventurers to go on quests to get new items.
The problem is this: In the current design, there's a major incentive to keep any one adventurer from growing too strong, so the other players tend to sell that adventurer mediocre cards to keep his deck slowed down. The player who is planning on hiring that adventurer will choose to "train" (read: trash some cards) or sell powerful cards to them, with the hopes of speeding that deck up... Therefore, with the current way the rules are set up, the typical strategy is thus to make every adventurer as mediocre as possible. I need a mechanism that forces the players to try to specialize/build up the adventurers at least to some extent, so that there's interesting conflict over which one to hire.
I was thinking about maybe a mechanism like Troyes, in which monsters with very specific victory conditions threaten the town and MUST be defeated or all players suffer some consequence...
Or perhaps a stock-like mechanism, where players can "sponsor" certain heroes, which can still be hired by other players, but will receive some reward for their success.
Any other thoughts about a good way to deal with this?
The sponsorship idea seems good, and likely to at least assuage the problem while adding another neat system to the game. However I am not confident that it would remove the tendency towards mediocrity of the decks...
Something else I was thinking of might, in combination with this, work out well.
A: Troyes-like "evil" cards which the adventurers must face, and who destroy buildings (read: remove options) if they're allowed to siege the city. They sit outside the city walls, causing spaces to be closed until they're defeated, and they require specialized heroes to defeat (basically they're only vulnerable to a certain type of damage, or something similar) and as a result, the players must work together to at least build up the hero who can fight the current most pressing threat outside the gates. (Additionally, players should get no benefit from slaying these monsters)
B: "Quest" cards representing trials that only a particular player can hire adventurers for. If these are public then it's pretty clear when a player is building towards one, so there'd be a decent chance of keeping him off of it by junking items in that adventurer's deck... if they're secret, then observant players can keep track of what's been sold to a particular adventurer, and imagine what the "Quest" might be. If they don't want to junk that adventurer, they can at least profit from the other player's effort by attempting to get related Quests, piggybacking off of the first player's effort.
I think that these, combined with some method of "protecting" an individual adventurer (perhaps each adventurer will only accept a certain number of cards, regardless) might help overcome the "gravity" dragging adventurers towards the middle.