If an opponent targets a unit with Deflect and pays the additional cost, then the spell is reacted to with Defy, does the opponent still lose the resources they paid for Deflect?

Ruling: Yes, the opponent still pays the Deflect cost. The additional cost from Deflect is paid when the spell is put on the chain, before any reactions can occur.

Sequence:

• Opponent plays spell targeting Deadbloom and pays both normal cost and Deflect cost simultaneously
• Spell goes on the chain
• Defending player can now react with Defy
• Defy nullifies the spell, but costs were already paid