As spoiled at the World Champion event in Eurpoe, The Endless Plains of the Unicorn has a trait:
"This Stronghold Produces 4 gold on your First turn."
It doesn't say that the Stronghold produces 1 less gold on your first turn just that it produces 4 gold. So I see a couple of problems with this.
1) It produces a total of 9 gold on turn 1 (4 gold from the trait and 5 for bowing the Stronghold) much like the Mantis Stronghold can produce 6
and
2) Sensei's that give -1 gp don't affect the 4 gold on turn 1 trait.
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