I have 0 available MU and my opponent has a rezzed piece of ICE with 0 strength. I install Parasite, hosting it on that piece of ICE. I now have a static card effect saying to trash the piece of ICE. I also have a game rule saying that I need to discard programs until I no longer exceed my maximum MU. What happens?

My friends and I assumed that the game rule would trump--and I would end up needing to discard programs before Parasite would trash the ICE--but I figured I'd ask to see if it's been clarified somewhere.

Parasite will not enter play until you have an MU available for it.

profligate said:

Correct. In order to install a program when you have 0 available MU, according to the rules, you need to trash a program during the same action window, while the new one is being installed.

That’s mostly true but rules say you can choose to trash any number of installed programs at the beginning of an install program action , but you don’t have to so there’s another rule that says if your MU is ever exceeds your mu limit then u have to trash down to your available limit. So basically you can choose to not trash when u install parasite and then let it trigger the mu exceeded rule as well as the parasite ability to trash the ice. Or have I been playing it wrong?

Gathrax42 said:

I think you've been playing it wrong. I believe the rule about trashing down to your available limit is for instances when your MU limit is reduced as a result of a card or action. Would be good to get this clarified by FFG though.

Gathrax42 said:

Playing it wrong. When your MU exeeds its limit, you must trash programs to bring your MU to allowed limits before the whole install can be resolved. Think of it in terms of installing a program on your computer. If you need 5GB to install it, and you only have 4.8, it won't install until you free up that last .2GB. The game mechanics for MU are extremely similar to this.

Thanks stormwolf27 that rely clarifys things for me, dont know why i didnt think of it as actual memory.

I see three relevant sentences in the rules.

"The Runner cannot have programs installed that have a combined memory cost greater than his available Memory Units (MU)."

"If the MU costs of the Runner's installed programs ever exceed his available MU, he must trash his installed programs until he is no longer exceeding his availble MU".

"The Runner can choose to trash any number of his installed programs at the beginning of an install program action."

I can see where you're inferring (and it's a fair inference) that you can't install a program if you don't have the memory for it; but I don't see that written in the rules anywhere.

Rules 1 & 2--taken together--would seem to suggest that you can install programs over your memory limit and are just forced to immediately trash down, which would create a simultaneous timing conflict with effects that happen on install and passive effects.

The existence of Rule 3 would seem to suggest that there is a rule that you need to have available memory in order to install a card--because otherwise there'd be no reason to trash programs at the beginning of an install program action (as an aside, this rule limits game space in that they can't make future Corp cards that host on Runner programs because they're basically unplayable without a "host program cannot be trashed" rider; so that suggests that this rule is meaningful). The idea that you can start an install and then have to trash down before the install completes seems like a misreading of this rule.

I was hoping for some clarification on the issue, but I guess I'll just email FFG about it.

AerysII said:

personally, I think you're over reading into this, but if you can't accept what we've said because it doesn't make sense to you, then, please do email ffg, and please post the response here in this thread.

AerysII said:

We already have a ruling by Lukas:

There was quite a bit of discussion about max MU, installed programs and card trashing. So I went ahead a submitted the 3 following questions to get an official answers to all angles of this subject.

1) If I have Akamatsu mem chip installed and 5 MU worth of programs. Can I use Aesop's Pawnshop to trash Akamatsu mem chip and then be forced to trash a program to bring my MU total down to 4 ? Or is trashing Akamatsu mem chip with Aesop is an illegal action because it create an illegal situation ?
2) On the same subject, is the corp allowed to use Powergrid overload to trash Akamatsu mem chip ? Or would it also be illegal because it create an illegal situation ?
3) If you are already at maximum MU usage, can you install a program anyways and then immediately be forced to trash a program to go back down to maximum MU usage ? Would it triggers "when a program is installed" triggers ? Or is it illegal because it create a illegal situation ?

Lukas Litzsinger wrote:
Thanks for the questions.
1. Yes, you can trash the Mem Chip and then trash a program to maintain a legal rig.
2. Yes, the Corp can trash the Chip and this may result in the Runner trashing a program.
3. Before you install a program you can trash any number of programs. So if you are at your max, you state that you are installing, trash anything to make room for it, and then install the new program.

Here the complete 3d: http://www.boardgamegeek.com/article/11168178#11168178