Legacy of Durin is a card that I think is overpowered, but not broken enough to receive an errata. For one lore resource, you should be drawing at least one card from this per round in the right deck. At least you don't get a card whenever you put a dwarf into play, or Legacy would be heading down the limit once per round express. This is a very powerful card and a staple for Dwarf decks.
Legacy of Durin
Attachment. Cost: 1.
Attach to a Dwarf hero.
Response: After you play a Dwarf character from your hand, exhaust Legacy of Durin to draw 1 card.
The Watcher in the Water #61. Lore.
It is reported that it has received an errata: now you need to exhaust the card to draw the card. — Ferreiraedy 1