I manage to get 7-8k DA against level 30 Joey. I used Buster Blader, The Dragon Destroy. The goal of the deck can be said in 5 steps. 1- Bring out The Dragon Destroy as fast as possible. 2 - Bring out a Buster Blader. Use Buster Blader the normal one to 🔥 off Joey's excess monsters. *Important* Make sure you always leave Joey with 1 monster on board. 3 - Wait till you have 0 cards left in your deck. 4 - Use Riryoku to half the normal Buster Blader. Than increase the Dragon Destroy. Than use Gift of the Martyr. 5 - Use the Dragon Destroy which is now super boosted to 🔥 off the last monster Joey has on field. It will do piercing damage of over 16k+ You don't need vassal or piranha. Thank You I hope this helps!