Activate Tawnos's second ability by paying 1, tapping it and sacrificing two artifact tokens, exiling Dominating Vampire from your graveyard and creating a token copy of it that is an artifact in addition to its other types.
When the Dominating Vampire token enters, it triggers, untapping Tawnos.
Activate Tawnos's first ability by paying 2 and tapping it, creating a copy of the Dominating Vampire token and causing you to mill two cards.
When the Dominating Vampire token enters, it triggers, untapping Tawnos.
Activate Krark-Clan Ironworks by sacrificing a Dominating Vampire token, adding CC.
Repeat from step 3.
This clever loop relies on Tawnos, Solemn Survivor acting as a factory for copies, using its costly second ability just once to jump-start the engine by exiling Dominating Vampire from your graveyard. Once that initial vampire token enters, its own entry trigger happily untaps Tawnos so you can begin churning out identical copies for a mere {2} mana using Tawnos's first ability. Whenever those extra bodies pile up, Krark-Clan Ironworks is right there to sacrifice them for raw colorless mana, funding the entire replication cycle while fueling the graveyard for more shenanigans.