@P_Hataway @mattcolville For you, what is unclear about the spell?
— Jeremy Crawford (@JeremyECrawford) December 13, 2016
@P_Hatawaya few things actually: if the creature makes the save, does it avoid both the damage and the restraint? Yes.
— Jeremy Crawford (@JeremyECrawford) December 13, 2016
@JeremyECrawford in other words, does the spell save occur the turn the spell is cast, if there is a creature within its area of affect?
— Jaron P. Hataway (@P_Hataway) December 13, 2016
Does creating an area of effect on someone mean they entered it? See Sage Advice Compendium (look for "Evard"): https://t.co/WWVq6Y8bNj #DnD https://t.co/ww5tuueWmc
— Jeremy Crawford (@JeremyECrawford) December 13, 2016
@P_Hataway lastly, I’m assuming that a creature would need to make the Dex save for every turn it starts in the affected area. Yes.
— Jeremy Crawford (@JeremyECrawford) December 13, 2016
Unusual situation I know… If Evard’s black tentacles is cast on the deck of a ship moving 20 feet per round, spell says its on the ground – does the spell move with the deck of the ship or hold its position in relation to the earth?
Unless you, as the DM, want to be a richard, it should move with the ship.