Primary: Wireless Dagger with maximum bounce upgrades. Optional weapons 3-4: Bananarang (double hit mechanic), Blood Magic (HP sustain). Due to bounces, can safely take multiple boss curses without risk.
Moldy Cheese (+40% poison chance) + Unstable Transfusion combo will instantly melt T3 bosses. Stack lifesteal from shrines (critical for survival). Blue/white microwave items mentioned in source but not in reference list.