1. Start a custom Dominion game.
2. Open the shop.
3. Select a Longsword or Recurve Bow. These items were the old recipe for the Lightbringer (as it currently acts on Live.)
4. Look at the list of items that build from these two items. The Lightbringer will be in the list for both items.
5. Select the Lightbringer. Note that it does not build directly from Longsword and no longer uses Recurve Bow at all.
As a side note, the shop DOES display Grez's Spectral Lantern and Pickaxe as properly building into Lightbringer.
Outside of that, I'll be testing for further bugs on Dominion. You might wish to link any you find here, so RiotNome can more easily see them.