The Untouchable medal is awarded to individuals after killing 25 opponents in a row without dying on multiplayer matchmaking, or after killing 50 opponents in a row without dying on firefight or campaign in Halo: Reach and Halo 3: ODST.
In Halo 3, ODST, and Reach, the medal is represented as a platinum and gold bulls-eye target sitting on top of a sixteen-pointed platinum star. In Halo 4 and Halo 5: Guardians, it was reduced to a eight-pointed platinum star.
- It has been proven that the highest spree possible is 255 kills. Even if you get more kills after that number, without dying, it will still say that your highest spree was 255 kills. This is most likely because 255 is the maximum value representable by an eight-digit binary number, and therefore the maximum representable by an unsigned 8-bit byte.