The Tough Luck is a collectible Golden Skull in Halo 3, as it is with the rest of the Golden Skulls this skull worths 10 Gamerpoints. Tsavo Highway campaign level, when activated the enemy will have a higher rate to evade your projectiles and weapons such as the Needler.
You can find this skull right next to a huge long pipes in a dead end bridge, just climb over the yellow ladders and you can find it in the next cliff gaping.
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