Can I reveal a hidden Teemo Scout at BF1 when my opponent attacks, then reveal Tideturner at BF2 and use its ability to swap positions with Teemo to save it?

Ruling: Yes, when you receive focus, you can reveal Teemo first (triggering its "When you play me" effect), then while still having priority, reveal Tideturner and target Teemo with its swap ability. Both effects go on the chain and resolve in reverse order.

Sequence:

• Opponent attacks into BF1 and passes focus to you
• You reveal Teemo, its "When you play me" trigger goes on the chain
• You still have priority, so you reveal Tideturner and target Teemo, adding that to the chain
• If no further responses, Tideturner resolves first and swaps positions with Teemo
• Teemo's trigger resolves (gains might)
• Chain empties and focus returns to opponent

Nuances:

• When an opponent asks "do you have a response?" during their focus window, they are shortcutting and effectively passing focus to you
• Proper etiquette is to explicitly say "pass focus" rather than asking if opponent has a response, as the latter can create ambiguity or enable meta-gaming
• The attacker should make their decisions on their own focus window without fishing for information