The recommended skulls for this mission are Tough Luck, Fog, Famine and Thunderstorm. Tough Luck is not much of a nuisance, especially with the 1.5 multiplier. The only consequence is the absence of easy grenade sticks. As with Fog, crowded battles like the one in the motor pool and Barracks could be a little fraught, but in this mission, being ruthlessly attacked from behind without beforehand notice is quite rare.