10. Sebastian Shaw Invades The Facility - First Class
Introduced in X-Men: First Class, Sebastian Shaw is one of the most powerful villains the team have had to face. Let alone a group of young, untrained recruits.
In an attempt to gain the upper hand on Charles Xavier, Shaw invades the government facility that is harbouring the new members of the X-Men. Shaw has the ability to absorb energy and then use it as his own power in the form of concussive explosions. This leads to an epic encounter with a young soldier who unloads a full clip into Shaw, but this proves ineffective.
Shaw then absorbs the blast of an RPG, absorbing it into himself. He then uses his ability to wipe out an entire team of soldiers before making his way to the young mutants.
Admittedly, this is a very one-sided fight but it shows how well the X-Men franchise can showcase their characters abilities as well as creating a menacing and formidable threat in the form of Sebastian Shaw.