Absol can have a ton of different movesets, but its crappy defensive stats ruin it. Also, if you want a moveset for Absol, please include whether it is for in-game or NB. That can make a big difference on its moveset. At any rate:
Absol @ Leftovers
Adamant Nature (+Atk, -SAtk)
- Fire Blast
- Return
- Shadow Ball
- Swords Dance/Shadow Ball
This is risky, but can be effective, especially if you can SD/Sub on a switch. Some people throw a Baton Pass on there somewhere too.