When I’m creating a custom monster, I try to make it as complete as possible. Yes, I make some adjustments at the table, but I would rather not have to if I can avoid it.
For this week’s session, I was playing around with two concepts. First, I wanted to include a solo that wasn’t part of a plotline. That is, I wanted a random “big bad.” I also wanted to set up a fight that included as many narrative elements as possible.
Behold, the Tundra Crab in all its might and glory!
I used a 4×4 dungeon tile to represent the monster.
This fight was a lot of fun, but it did require a large number of GM’s calls:
“I want to running jump on top of the 15′ crab.”
“Can I tunnel into the snow?”
“When it burrows with me on top of it, I go with it?!?”
I think you get the idea. The point is, don’t be afraid to let your players try crazy stunts.