We all know that the mechanist is actually the Lone Wanderer who took the burden of the costume from Scott Wollinsky in Canterbury Commons and has come to the commonwealth for his ultimate face-off against the Silver Shroud and Manta-Man.

I'm pretty sure the Mechanist is actually... ya know the mechanist...

Then i am expecting a new DLC called AntMatron.

"The antagonizer has brought her crawling horde of ants to the footstep of the commonwealth! Assemble your army of stingwings and face off the ultimate enemy in a battle of unseen magnitude."

I don't expect a TON of work to go into the related quest but I'm sure it'll be interesting.

It was the butler. It's always the butler.

It could be none other than Old Man Jenkins!

Colonel Autumn in the derelict subway terminal with the deathclaw gauntlet!

Wait...

It's Butch - trust me! Had a chat with Todd and he told me...... .....TRUST MEEEEEEEEEEEEEEE!!!!!

I thought it was Water Beggar in The Citadel with the Tire Iron

It's the Courier's brain. They had a falling out after the events at Hoover Dam and went their separate ways. Then the brain had itself put in a robot body and called itself the Mechanist.