In 5th edition Dungeons & Dragons, I am playing a Sorcerer where I have set myself the rule that I can never take fire spells, and instead take weaker spells and try to make the most of them with creativity. I am wondering if the following trick works.
The Wall of Water spell has the following wording:
Spells that deal cold damage that pass through the wall cause the area of the wall they pass through to freeze solid (at least a 5-foot square section is frozen).
If I use the Quickened Spell Metamagic option and cast Wall of Water into a creature's space as a bonus action, then as an action cast a Ray of Frost cantrip at the creature, will that freeze the water and trap the creature inside a block of ice?
Best Answer
Frozen
This is a great combination! The rules for casting two spells with a bonus action and action simply state (PHB, 202):
In your example, you have used your Bonus Action via Metamagic to cast Wall of Water. There is no save for wall of water; it only creates battlefield control aspects within its area.
Should you cast it on a space containing a creature, that creature would be within the Wall (although do note the Wall is only 1' thick.) Also note that only the 5' section of the wall they are in (see below) is turned to ice (and if destroyed, does not refill with water.)
The creature is now in 1' of water and the follow-up Action Cantrip of Ray of Frost interacts beautifully with Wall of Water's cold damage response:
You'd now have a Wall of Water with a frozen section containing a creature in their 5' space (but only 1' thick of ice.)
But what can a frozen creature do?
This is going to likely get table-dependent. There are no rules with regard to being 'in ice' and what conditions that imposes (like Restrained or Grappled.)
How I'd rule
I'd likely give a Dexterity save to avoid the ice (DC set by the caster, much like with Wall of Stone trying to entrap someone) and then upon failure give them the Restrained condition.