It is clearly stated in the rules that Memory Units (MU) only apply to 'installed' programs. By 'installed' I mean installed on the runner's rig.

Then I read the ZU.13 Key Master card:

[...] the memory cost of ZU.13 Key Master is 0, even if it is not installed.

This seems to imply that a program's MUs count even when not installed. As if they would count in your grip. Nothing in the rules supports that.

Can someone explain this card please?

1 Answer 1


The reason for the "even if it is not installed" language is to allow you to install ZU.13 Key Master even if you are already at your MU limit. You are of course correct that cards in your grip do not count against your MU limit.

To explain formally: p. 6 of the rulebook states:

Cards in the grip are inactive

and from p. 4:

An inactive card’s abilities do not affect the game

So without that phrase, ZU.13's ability to not cost MU would not work until it was already in play, and if you were at your MU limit, you would still have to trash some other installed program before you installed it. With that phrase, the card's intent is achieved, which is that it "costs" 0 MU as long as you have at least 2 link strength.

  • This also could be used for future cards that will tutor for breakers. Say another Rosetta 2.0 that cares about the MU cost difference rather than the cred cost difference [install a program with half the mu cost rounded down] allowing you to search out cloud breakers when you have the link.
    – Andrew
    Commented Dec 30, 2017 at 18:32

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .