Upon activation, Isaac will raise Tammy's head in the air, and it will fire 10 large tears in a circle around him, damaging enemies within range.
- The tears will have all attributes of Isaac's normal tears like speed, size, damage and special effects (like petrification poison, homing etc).
- Tears do not turn into Brimstone lasers, Technology lasers, Mom's Knives, or Dr. Fetus bombs or any other tear-changing item.
- When used with Wiggle Worm, instead of shooting in eight directions, it fires 2-4 shots per direction in the four cardinal directions.
- With A Lump Of Coal, Tammy's Head tears will start out at Isaac's base damage and go up as time increases (same as the normal Lump of Coal), instead of doing their normal huge damage.
- With Chocolate Milk, uncharged uses of Tammy's Head deal no damage. Charging shots allows Tammy's Head to deal damage again.
- Wiggle Worm forces cardinal direction shot grouping on Tammy's Head.
- Tammy is named after one of Edmund McMillen's cats.