This isn't necessarily comic book related other than I'm lifting the "Legion of Doom" name for this.
The challenge: Pick at least five villains from movies that came out over the past ten years and form a "Legion of Doom" who would make a formidable, nefarious alliance.
Davey Jones While I thought the second and third Pirates of the Caribbean movies were on the weak side, Davey Jones was an awesome character and a worthy addition to the pantheon of movie villains. He was a well-designed creature and the accent alone makes those movies worth watching. Having shown the ability to lead a crew of crazies, he'd take charge of this team.
Darth Maul The only character to come out of the Star Wars prequels who held any interest with me. This is probably because he was largely mysterious and didn't last long enough for Lucas to ruin him. He'd be the group's "ninja." Agent Smith While a computer program, he'd fill the role of the spiritual or supernatural villain since supernatural beings were glitches or other programs in the Matrix. I suppose his inclusion means this entire story must take place in the Matrix which would explain how they all get together in the first place I guess. From that standpoint, he might be the most powerful enemy on this team.
The Operative Although he was the antagonist in Serenity, he may be the one in this group farthest from the villain mold. While he is ruthless and single-minded, the Operative would have to believe that teaming with this group was for a greater good. He'd ultimately lead to the undoing of this group because his values would eventually diverge with the rest of the group and he'd be forced to do what he believed was right.
The Green Goblin Though slightly insane, the Goblin is cunning and a technical genius. OsCorp would be the source of any tech that this group needed.
For added kicks, I think it would be awesome if this group had possession of a Cloverfield creature.
Who would they fight? I don't know. Doesn't matter. The bad guys are almost always more interesting than the good guys. But I suppose this post might be at least the start of a good list of "Superfriends."