Flooded combat rooms in trial chambers

Aquatic rooms or flooded zones of the chambers would add extra difficulty and variety, there might be drowned in the trial spawners (there may have tridented drowned to add some ranged dangers) and there should be magma blocks for respiration, or more complex structures that have aquatic and normal enemies. This would also mean you have to be well prepared to enter chambers and not just go with the boring sword everyone used