Stardust Dragon/Assault Mode can negate the effects of all commonly played monster cards, including Honest, Blackwing Kalut the Moon Shadow, and Destiny Hero Malicious. It can also negate commonly played spell cards like Solar Recharge and Destiny Draw. He took advantage of that fact while building his Deck and is hoping his decision pays off today.
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Related The decks alt Commander, Carmen, Cruel Skymarcher seems perhaps slightly overcosted at first, but does good consistent work for the deck if you can protect her from removal
"Harr, Generaider Boss of Storms" can force the opponent to send 1 monster from their hand or field to the GY if they draw cards outside of their Draw Phase
But thats enough for the price to move up, especially on that extended art variant, which looks gorgeous