A novel about people playing a tabletop RPG get pulled into the world. They have gauntlets on their arms with dice that roll for outcomes. One character was a berserker type and he had a small flying dragon with him.
The book you describe is one of Andre Norton's worst books (and the very first Dungeons and Dragons novel so far as I know), Quag Keep.
Once, they were role-playing gamers in our world.
They came from different places and different backgrounds.
Now they're summoned together by some magical force...to a land that mirrors the games they used to play.
Quag Keep. Can they band together to unlock the secret of their summoning--and rescue from the legendary Quag Keep the person who may be able to return them home?