SWC Most powerful sith lord

Post your arguments on why your chosen Sith lord is the most powerful, including:

Appearance:

How often does your Sith appear, in games, movies, and TV shows, how important is he/she to show up more than once?

Battles:

What battles has he/she won?
Who has he/she won them against?
By how much did he/she win?
Does he/she seem to come back from the dead?

Combat skills:

How powerful is he/she with the force?
What is his/her combat skills?
How cunning is he/she?
What tricks does he/she have up his/her sleeves?

Allies:
What was/is his/her position among the sith?
How many allies does he/she have?
What kind of allies are they?

Remember to be respectful and have fun, and don't forget to vote for your chosen Sith!

 

This is an older thread but it checks out.