That said, some cards exceeded my expectations, like Corpse Appraiser or Giada, Font of Hope that had opened the door for new strategies to shine
702.118b You choose which creature to sacrifice as you choose to pay a spells emerge cost (see rule 601.2b), and you sacrifice that creature as you pay the total cost (see rule 601.2h)
One of the godfathers of Magic writing, Jamie Wakefield, famously championed his Mono-Green Secret Force, for extremely hip battling with Natural Order fueling Turn 3 Verdant Forces
Once you announce that you're casting Lumbering Megasloth, no player may take actions until you're done casting it
The card basically reads as "if your opponent takes game actions, you draw a card, oh hey, and also, no looping extra turns over there, guy." That's under normal game conditions, mind you