Fetch failure

I had a deck with Danitha Benalia’s Hope, Blade of Shared Souls, and no other Equipment or Auras in it.

Somehow during a game I managed to cast my first Danitha late enough that I had all 4 of my Blade of Shared Souls in the graveyard (along with 7 other cards). (Not 100% sure how they go there but my Planeswalker was Dakkon, and I also played with Overlord of the Floodpits, so there were plenty of ways I could put cards in my graveyard myself even before Greg started doing it for me)

Cast my first Danitha of the game: She failed to fetch a card.
Cast my second Danitha of the game: She failed to fetch a card.

That’s not right, is it? If a card tries to fetch a card from a library, and there are 0 copies of it remaining in your deck currently, then the game should add extra cards to your deck so that it does now contain a legal fetch target. That’s how many other cards in the game work now: Deploy the Gatewatch, for example, in decks with HUF and/or Omni, are capable of playing dozens of copies of Deploy without failing to fetch any cards. Many fetch cards in Legacy are capable of going into infinite loops.

I’ve had this happen a few times when I had Assimilation Aegis in my deck. I couldn’t repeat the bug so didn’t report it, but I can validate what you’ve observed.

Just had Daxos the Returned’s 1st ability fail to fetch an Enchantment. I’m sure that this is because all the copies of any Enchantments I could have fetched are not currently in my library: I am only playing with one Enchantment (Dollmaker’s Shop), and there are 2 in my Graveyard and 2 in my Exile.

Oh! But on the next turn, when I used Daxos the Returned’s 1st ability, (still with 2 DS in my graveyard and 2 in my exile), the ability did correctly fetch an Enchantment.