Cemetery Prowler is one that I find particularly strong, and one I love to play in Commander, especially (which is probably why its a Mythic, lets be honest)
The bad part is that you can search your whole deck and tutor a Llanowar Elves
Hers is potentially one of the most powerful companions for a Doctor Matters deck, giving you card advantage just for playing the huge number of cards that are either a Doctor or have Doctors companion (this sets version of partner)
[one_fourth stack="responsive"] [/one_fourth] [one_fourth stack="responsive"] [/one_fourth] [one_fourth stack="responsive"] [/one_fourth] [one_fourth_last stack="responsive"] [/one_fourth_last] [one_fourth stack="responsive"] Bontu the Glorified [/one_fourth] [one_fourth stack="responsive"] Gonti, Lord of Luxury [/one_fourth] [one_fourth stack="responsive"] Razaketh, the Foulblooded [/one_fourth] [one_fourth_last stack="responsive"] Tetzimoc, Primal Death [/one_fourth_last] [one_fourth_last stack="responsive"] [/one_fourth_last] [one_fourth_last stack="responsive"] Yahenni, Undying Partisan [/one_fourth_last] Standard Legendary creatures currently have a wide range of abilities and mana costs for these black Legendary creatures
Cards like Path to Exile are an option, but so are color-intensive removal spells like Void Rend
Thats enough to control almost all remaining game actions, assuming youre in a 1v1 situation