Does Rek'Sai, Breacher come accelerated with no additional cost when played from the champion zone, counting herself for her own effect?

Ruling: No, Rek'Sai does not count herself for her Accelerate effect when played from the champion zone. Her passive ability does not become active until after you've already decided whether to pay the Accelerate cost, and you must still pay the Accelerate cost (1 power of the card's domain and 1 energy).

Sequence:

• Decide whether to pay Accelerate cost when playing Rek'Sai
• Pay the cost if choosing to Accelerate
• Card enters the board
• Passive abilities become active during the Resolve step

Nuances:

• Rek'Sai's Accelerate passive does not make Accelerate free; it still requires payment of 1 power of the domain and 1 energy
• Passives don't become active until one of the first steps of "Resolve" in FEPR (after the card is already on board)