Ugly is only Skin Deep is an Achievement in Halo Wars that is worth 70 Gamerpoints. It is obtained for beating Act 3 on any Difficulty. Act 3 consists of the missions Anders' Signal, The Flood, Shield World and Cleansing.
- The phrase "Ugly is only skin deep" is a reversal and reference to the saying, "Beauty is only skin deep."
- The name of the achievement is a play on a famous adage about beauty, and is a reference to the Flood, which are first encountered in this act.