Hammerwatch had Steam trading card support added on November 12, 2013. There are 5 cards in the series, 3 of which you'll receive for purchasing and playing the game.
Trading Cards
Foil Trading Cards
Badges
Level 1
Stone
Stone
Level 2
Jade
Jade
Level 3
Bronze
Bronze
Level 4
Silver
Silver
Level 5
Gold
Gold
Foil Badge
Castle
Castle
Emoticons
:1up: (uncommon)
:bkey:
:ipot: (uncommon)
:mana:
:plank: (rare)
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