Tsunami in a dungeon?

[MarkVIIIMarc]

Just reading some of the spells here and came across Tsunami. My first thought is it is absolutely made to destroy an advancing army in the field. What would happen though if you cast it in a dungeon setting? Would the waves spread from room to room in as realistic manner? Would they bounce back a bit?

One of my thoughts is if the wave can't be 300 feet tall it will be however tall it can be and maybe 340 feet thick. That doesn't seem RAW though and would make it a 6D10 then 5D10 then 4D10 and so on repetitive damage for folks who fail to swim through it.

How has this gone at your tables?

[JackPhoenix]

RAW, you can create Tsunami in dungeon, but it's a waste of spell slot. It'll be as tall and long as the corridor allows, still 50' thick, and the creatures caught in it will take 6d10 damage. It'll move 50' at the start of your next turn, causing 5d10 damage to any creature caught in it, it won't damage objects, so first wall or closed door will stop it, it won't go around corners, and if it's less than 51' tall, it'll end at the end of the same turn.

Funnily enough, if it *is* 51' tall, the 1' of water left in the 3rd turn will still be enough to move any creature up to huge size, and cause 4d10 damage.