You can keep one in inventory as you kill d clone.
Identify new annihilus, leave the best one.
Remember game name and password.
Make a normal game, drop carried annihilus on ground.
Make a level 1 mule, rejoin normal game.
Pick up annihilus with level 1 mule.
Rejoin hell game with high level character.
Pick up new annihilus.
A little bit risky but it works for solo play.