Coming in at #10 is a card that I have been relentlessly trying to work out in standard. Unfortunately, I never felt like Red never really had the perfect 5 drop to abuse Generator Servant with.
Currently, I still think the best synergy with Mr. Servant is my #9 pick for cards I will miss after 2015 Rotation: Underworld Cerberus
By casting a turn 2 Servant into a turn 3 Cerberus you effectively create a 6/6 haste with evasion with the added bonus of at least getting back a Generator Servant if the Hound dies. Here is the decklist threw together:
This deck is packed full of synergies with both Underworld Cerberus and Generator Servant. For the Servant, you can also ramp into a fast Whisperwood Elemental that feels like a more beefy Goblin Rabblemaster. Surrak, the Hunt Caller and Xenagos, God of Revels are alternate ways to give the Underworld Cerberus the haste that it desperate needs in this format. For a more complete overview of the deck, check out the decktech on youtube: