Tactics for Necropolis.

if there's air, then yes, the slow effect is removed... although it's a pity to have to follow someone else's lead – it's more enjoyable to use some kind of explosion –))))
Water magic, in addition to prayer and teleportation, has a global dispel ability, which sometimes comes in handy, and it also has a clone ability, which is also pretty good. Therefore, I think it's worth taking water when playing as a Warrior – it's not a given that you'll get air in the near future.