"Roleplaying game supplement"--Cover.
"For use with these 4th edition Dungeons & Dragons core products: Player's handbook core rulebooks, Dungeon master's guide core rulebooks, Monster manual core rulebooks, D&D miniatures, D&D dungeon tiles."--p. [4] of cover.
"d20 system"-- p.[4] of cover.
Hammerfast : a dwarven outpost adventure site by Mike Mearls. ISBN 9780786955343. Published by Wizards of the Coast in 2010. Publication and catalogue information, links to buy online and reader comments.