If another effect (or effects) modifies how much damage a source would deal to the chosen player or a permanent they control (for example, by preventing some of that damage), the player being dealt damage or the controller of the permanent being dealt damage chooses the order in which any such effects, including the effect of Sawhorn Nemesis, apply
Nice addition to the game
Plan your attacks carefully and dont be worried about picking on the player with no creatures in play
Effects that modify a creature's power and/or toughness will apply to the creature no matter when they started to take effect
However, one-mana tutors that can search up a wide array of cards are some of the most efficient out there, and like Seedborn Muse This card causes you to take what is essentially, when built properly, three additional turns worth of effects each turn cycle
Ok Perdita - Playful Mother #21 (Lorcana Promo) Details All prices are the current market price