You should only play Intervention Pact in decks built to force another non-white player to cast the card, using something like Hive Mind to force the upkeep trigger on someone else
If you see a Greasefang, Okiba Boss, all the better
C Common Legendary Six Samurai - Shi En X DARK Level 5 [ WarriorSynchroEffect ] ATK 2500 DEF 1400 1 Warrior Tuner + 1+ non-Tuner "Six Samurai" monsters Once per turn, when your opponent activates a Spell/Trap Card (Quick Effect): You can negate the activation, and if you do, destroy it
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Also, I can just give cards like Deafening Silence around the table to opponents who dont have a sacrifice package to draw cards later
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