Repel Gel

Repel Gels are rare items found in the game Paper Mario. The gel makes Mario invisible for three turns. They are dropped by ? Mark Li'l Oinks and only appear in a few select areas, such as Jr. Troopa's Playground after smashing the Stone Block there after Mario acquires the Super Hammer, in a Question Block in Gusty Gulch, and by paying Rip Cheato sixty four coins for the fourth time.

In Paper Mario: The Thousand-Year Door, the Repel Gel was replaced by Boo's Sheet, which is a much more common item.