Interaction and Combos
Ignacy Trzewiczek writes about interaction in his upcoming boardgame 51st State. What I find interesting is his distaste for negative interaction in a combo game; the attraction of a combo game is in assembling and exploiting the synergies - having opponents interfere with them could be extremely frustrating.
Supporting Trzewiczek's view, the deep-combo game Race for the Galaxy contains very little negative interaction. Its takeover mechanic allows dismantling of existing synergies - the effect of this varies and can be an irritant or a devastating reversal - but takeovers are fairly rare.
When they do occur, scoring synergies rather than functional synergies tend to be disrupted - you lose points rather than losing powers and options. In Race for the Galaxy, functional synergies tend to be immune to attacks (as powers reside on developments cards - technologies - rather than the vulnerable worlds).
There is another element: robustness. Despite its reputation for being "multiplayer solitaire", Dominion contains very powerful negative cards - Thief, Pirate Ship, Ghost Ship, Rabble, Swindler, Saboteur, Possession, and so on, all of which disrupt the functional synergies in your deck. Setting aside irrational complaints about those cards, the discard-and-redraw mechanic allows you to recover between turns, and the flexible card powers allow you to deploy tactical combinations despite attacks. Similarly, the shallow-combo game Innovation contains lots of flexible powers, so doesn't rely on specific conjunctions of cards; after being attacked you'll still have options.
Supporting Trzewiczek's view, the deep-combo game Race for the Galaxy contains very little negative interaction. Its takeover mechanic allows dismantling of existing synergies - the effect of this varies and can be an irritant or a devastating reversal - but takeovers are fairly rare.
When they do occur, scoring synergies rather than functional synergies tend to be disrupted - you lose points rather than losing powers and options. In Race for the Galaxy, functional synergies tend to be immune to attacks (as powers reside on developments cards - technologies - rather than the vulnerable worlds).
There is another element: robustness. Despite its reputation for being "multiplayer solitaire", Dominion contains very powerful negative cards - Thief, Pirate Ship, Ghost Ship, Rabble, Swindler, Saboteur, Possession, and so on, all of which disrupt the functional synergies in your deck. Setting aside irrational complaints about those cards, the discard-and-redraw mechanic allows you to recover between turns, and the flexible card powers allow you to deploy tactical combinations despite attacks. Similarly, the shallow-combo game Innovation contains lots of flexible powers, so doesn't rely on specific conjunctions of cards; after being attacked you'll still have options.