Like any strategy revolving around graveyard interactions, this build is pretty easy to sideboard against
Gae Bolg Equip Artifact - Equipment Warrior's Sword Job select (When this Equipment enters, create a 1/1 colorless Hero creature token, then attach this to it.) Equipped creature gets +3/+2 and is a Warrior in addition to its other types
Amulet can produce some lightning fast kills, but also has access to Bojuka Bog, which they can also pick up with bounce lands to effectively lock Dredge out of the game
Since your entire deck is (mostly) made up of Assassins, just one Assassin dealing damage gives all your Assassins freerunning , which lets you cast them for just two black mana
When a Pokmon that is Asleep, Confused, Paralyzed, Poisoned, or Burned retreats to the Bench, these effects are removed from it