The Plan / Splitting up is always the right answer is the twenty-second level of Chapter 4.
Dialogue
Amy Pond: So you're saying that if we can find this piece of Cyberman technology, we can disable all Toclafane?
Brigadier Lethbridge-Stewart: That is correct, young lady.
Clara Oswald: Wherever they are in space and time?
Brigadier Lethbridge-Stewart: The Doctors seems (sic) to think so, and I don't have any reason to doubt them. They certainly were using some big words, and gesturing a lot. Apparently we hook this cyber-gadget into the TARDIS time circuits, or somesuch, and she will do the rest. Every one of the Toclafane, no matter where they are in time and space, will be zapped.
Twelfth Doctor: Everyone gather around, we have a plan.
Ninth Doctor: We need a piece of Cyberman technology, it's rare - A tellurian transformer from a Cyberman info-stamp, but there's a chance we can find it wherever we can find a Cyberman.
Eighth Doctor: We should split up, cover more ground. Time may be relative, but it's still counting down.
Third Doctor: I've had some run-ins with those horrible creatures, I'll go back to my time. Brigadier, why don't you come with me?
Brigadier Lethbridge-Stewart: If you insist, Doctor.
Twelfth Doctor: I'm going to poke around my timeline a little. Clara, River, let's take a walk around London.
Second Doctor: (A deeply sad look in his eyes) Cybermen always give me the shivers. Organic matter underneath all of that...circuitry and hydraulic fluid. Emotion as a weakness, metal and z-bombs. So, will you be heading off to Antarctica then?
First Doctor: I never met...do you mean I meet these cyber-creatures later in my timeline?
River Song: Spoilers, sweeties.
First Doctor: Then if they are part of my timeline then yes, yes I must go at once.
Eleventh Doctor: Remember - take something gold. Cybermen aren't overly fond of gold.