That ability unlocks combos with +1/+1 counters and extra combat spells, especially in go-big aggro strategies
If an opponent has been setting up for a powerful turn, but you rip the cards right out of their hand, theyll have nothing to do on their turn, putting them behind several turns
Its power and toughness are equal to the amount of cards in your opponent's graveyard, and if you have been milling them each turn before casting this, that number could be quite high
Spectral Sailor is your best one-drop, and probably would be even if it was just a textless 1/1 flyer with flash, but its card draw ability is dramatically more relevant than you might realise at first, as it helps you pull ahead in card advantage in the games where your Curiosity-effect engine is broken apart
Prices typically peak during prerelease weekend and drop 20-30% within the first 2 weeks of wide release (July 24)