In the case of successful run via the Legwork how the runner should access cards? Should he take them all at once? Or he should take one, return it back into the Grip, and take another two attempts?
You access the cards one at a time, but they don't go back to HQ until you're done.
Essentially, you draw one from HQ, decide what to do with it (if anything), then set it aside as you draw the next card. Once you're finished, the cards go back to HQ (unless they don't for whatever reason).
From the FAQ, page 3:
When the Runner accesses multiple cards from HQ, the cards are accessed one at a time, and do not return to HQ until the Runner is finished accessing.
If you want to trash the cards, you must do so as you access them one at a time, not after you've accessed additional cards.
The cards are accessed one at a time, all decisions about the currently accessed card are made, then the next is accessed. When this access finishes all cards are returned to HQ at once.
This matters for several reasons:
- Leela Patel - If you access an agenda with more cards to access, the effect of leela happens before you access the rest, any unrezzed card you return with Leela is now possible to access.
- Trashing - You trash the cards when you access them, a runner with low credits might not trash something that they see early due to the cost because they are afraid of what else they will see later being worse.
- Optional costs - Effects like Obokata Protocol have to be decided on immediately, choosing to take the 4 damage runs you the risk of hitting cards like Snare! later in the access. If you accessed them all at once, you would know not to steal the Obokata since there is other damage coming.
- Haarpsichord Studios - The effect of this ID prevents the runner from taking multiple agendas in one turn, this means they must steal the first one they access (unless there are optional costs they decide not to pay) they cannot see all those that are in their access and pick the best one to steal.
Some of these are moot points depending on the type of access, Information Sifting for instance the cards that are to be accessed are chosen all at once, then accessed one at a time, so Leela wouldn't matter.