Cross Poison\Sludge Bomb-STAB,both have good accuracy,I would go for Sludge Bomb because it has a bit more power than Cross Poison and has a 30% chance of poisoning the foe instead of 10% like most other poison moves.Then again,Cross Poison does have a high Critical hit ratio.
Dark Pulse-Good Power,good accuracy,STAB.You could have Crunch instead,though.
Ice Fang-Deals with Ground types,chance to flinch or freeze.
Earthquake\Hyper Beam\Giga Impact-Moves ike these might help with emergencies.Like if other moves you have are no good on the foe.
OR
Toxic\Swagger-Lets say your Drapion is low on HP and you think he'll go down on the next turn.Well if he has high speed,you may want to give the foe somthing to remember him by.Bad Poison,Confusion or other things like that.