Need some advice in high level group...

[Qvintus]

Say you dont trust how ever the party has who guards the item and build a doungen with the rest off the players to guard the part's...
and then you have secured all the item's teleport in (in the small cave no one know arbout and passe wall out to the doungen all the prity part) and the team have given you all the part's in one secure location and they cant stop you
Embrace you evil side and make som rediculse master plan...

 

[Herobizkit]

*LOL* @ Quintus... that's a great idea!

Manufacture some cockamamie dungeon that you know all the tricks to, then send the PC's in, separate them, and bump them off one by one. It would take some time (or a wish spell), but it'd be worth it.

 

[Bront]

Well how about pretending you don't have it anymore? Hide it somewhere secure (say, on another plane, or something) and say it was stolen (guess this only works if you aren't lawful though, as lying may violate your alignment).

Just because you're lawful doesn't mean you can't lie, just that you can't just randomly lie, that your lies usually have a defined and planned purpose.

 

[Krafen]

You have been playing with these characters for a long time, so you should have a good idea of their weaknesses. Don't wait for them to come after you, strike first! Pick them off, one by one. Think about who is the greatest threat. Not necessarily who you would have the hardest time fighting, but who has abilities dangerous to you. For example, will the party be relying primarily on one person to track you down? You should certainly have means at your disposal of destroying someone with no hope of resurection.

I really have no idea what the game plays like at level 50-60. One idea which comes to mind is abilities and immunities often come from magic items. Creatures like the nightstalker can permanently destroy magic items.