My four followers and I had a river incident.
We were but four elves and a dwarf heading south of the snow-covered mountains, and we finally come across a lovely river teeming with life: alligators, snapping turtles, camels all around.
I thought, hey, maybe if I stay near the shore I can learn how to swim provided my friends chill and don't come near.
Well, the elf with the crossbow decided that snapping turtle had it coming, and shot it, injuring it but not killing it.
The turtle gave in to the pain and passed out at the bottom of the river.
And then I saw the dwarf run in there, waving his mace above his head.
Plunk.
All that steel and iron armor is not buoyant as it turns out, and he started floundering in the water.
I only had a moment to consider how to get him out. I was hoping he'd get out on his own. But something else happened before he or I could do anything about it.
The river suddenly and instantly froze solid. The sun was beginning to set and the temperature dropped.
Bam!
The dwarf got encased in ice.
I started a bunch of campfires on the ice, that didn't accomplish anything.
We camped out beside the river to see if it would melt the next day, maybe fish his body out and get the nice armor off him.
Turns out, the river did unfreeze shortly before noon. Both the dwarf and the turtle were long dead.
And while I was stacking my gear in a nice pile to make it easier for me to swim with less of a load, one of the other elves (the crossbow-wielding idiot) jumped into the water before I did. Not even sure why, but he ended up floundering in the same exact spot as the dwarf. Did he see something shiny?
Thinking quick, I ran over and tried to do a wrestling move, to grab him by upper torso and throw him out of the river.
That almost worked. I grabbed him, ignoring his protests, and then received a crossbow bolt in the chest.
Thankfully that steel breastplate was still on and it got deflected.
The throw did not get the jerk out of the water, and he drowned a few moments later.
The remaining three elves fled from the river, before it had a chance to take more of them to its icy depths.
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The most painful part is that I took most of the day looking for steel and iron gear for these guys, visiting no less than three fortresses to outfit them for adventures. They were fully decked out in the best barter stuff available.
Lesson of the day: Shift-P tells you how cold the air is. If it's freezing, stay the hell away from water.