The Master, Mesmerist

{T}: Target creature an opponent controls with power less than or equal to The Master's power gains skulk until end of turn. Goad it. (A creature with skulk can't be blocked by creatures with greater power.)
Whenever a creature with skulk deals combat damage to one of your opponents, put a +1/+1 counter on The Master and draw a card.

Doctor Who

If an effect instructs you to choose a creature type, you may choose Time Lord.

Neither "Time" nor "Lord" are creature types. Some older cards were printed with the subtype "Lord," but all of those cards have updated Oracle card text that removed that type.

Unlike other creature types in Magic that are each only one word, the two words "Time Lord" represent a single creature subtype. Time Lord is the only two-word creature type.