Ok, lets go:
- Drop Rate of Falcon Items on Mini-bosses: 1 : 2,500 (there is a post from CM confirming this, but I cant find it now)
- Drop Rate on Cobra Mini-bosses: Unknown
- Drop Rate on Oberon: 1: 200
- Drop Rate on Scarlett: Unknown
On Falcon Castle you CAN trap every falcon in rooms (the only exception is the roof) and run freely from boss to boss, I'll show a map on where I trap them:
Rooms marked as YELLOW, is where you have to trap the Falcons
SURFACE:
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+1
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+2
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+3
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+4
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With this you can run from boss to boss and you'll only met falcons at the roof.
.
My route is:
- Island
- Table
- Monk
- Roof
I'd say Cobra bosses seems to have a much higher drop rate, and they also feature the Ugly Monster
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which can drop basically every cobra item, and it seems to be higher chance than even the bosses themselfs.
So, if I had to choose, I'd camp Cobra Bosses.