Underwater and Verbal spells/command words
Post date: Aug 16, 2019 4:8:51 PM
What happens when you are underwater and want to cast a spell or activate a magic item with a command word?
Creatures with Water Breathing: There is no penalty for speaking underwater.
Creatures without Water Breathing: You can cast a single spell or command word underwater, but afterwards you begin drowning. You're no longer holding your breath (and now on Con modifier rounds).
A creature can hold its breath for a number of minutes equal to 1 + its Constitution modifier (minimum of 30 seconds).
When a creature runs out of breath or is choking, it can survive for a number of rounds equal to its Constitution modifier (minimum 1 round).
At the start of its next turn, it drops to 0 hit points and is dying, and it can't regain hit points or be stabilized until it can breathe again.
Each turn, the creature must make a death save. There is no chance to stabilize while underwater.
For example, a creature with a Constitution of 14 can hold its breath for 3 minutes. If it uses speaks while underwater, it starts suffocating and has 2 rounds to reach air before it drops to 0 hit points (and thereafter needs death saves to survive).
That large, bolded part of the rule is the most important aspect of this situation. If a druid casts healing word on a character before suffocation's dying effect kicks in, they're back in the fight. If not, healing word fails to revive them - someone must help them breathe first.