I'm not sure what the hope would be there, or what a reasonable workshop/silkroad/island strategy is....
But I made one up, and it beats envoy whether facing off with 2 or not.
But if we're just looking for 3-player oddities...how about this one:
Ironworks/Island/GH beats IGG/Gardens 87%-13%
If we go 3-players, and 2 people try to go for Ironworks/Island/GH vs a single IGG it's even worse: IGG loses .5% to 45% (for the Ironworks players)
OTOH if that third player goes IGG it wins 33% to 15%, with a good 18% becoming ties (presumably for IGG)
So, it's like the inverse-prisoner's dilemma.
Testing a bunch of different strats...lalalala
Okay, here we go: Witch vs Chapel/Minion
So Witch beats Minion/Chapel all on its own 65%-33%
But, if 2 players try to go Witch, then a third player can do Minion/Chapel and win 40% of the games (vs 28% for Witch)
But then if one of the Witch players decides to switch to Minion/Chapel to get in on the action, the remaining Witch wins 52% of the time (vs 22% for the Minions).
What if the Witch player tries to do an Engine, since they have a Chapel available? It still goes to the one that picks a different strategy...
1 Witch/Village/Chapel vs 2 Minions/Chapel wins 62% to 18%
But 2 Witch/Village/Chapels vs 1 Minons/Chapel loses 29% to 41%
So, there you go pops...you can still dream.