[Spooky]

I have a campaign arc going that has the runners being paid by corp a to provoke corp b and c into war with each other. The table likes to blow things up/brick the opfor/electrocute the opfor. Their last two missions involved 1) going to corp b's security guard training camp dressed as corp c's agents and doing damage until they provoke a response, and then 2) going to corp c's military base dressed as corp b's agents and doing even more damage. Both times they succeeded very nicely, due to good tactics and prep on their part.

Question is, where do you think corp a is going to ask them to go next, to do what, that makes this fake corp war heat up? And btw, the runners have yet to figure out who corp a is, even though the face recognized the johnson as employing them for all 4 missions so far. I am having some trouble figuring what the runners would get tasked with next that won't TPK them in short order. And I am being deliberately vague because I don't know how many of my players read the forums.

Thanks for your ideas.

[JimmyCrisis]

My next few runs would be;
 1) assassinate, kidnap or otherwise incapacitate the leadership at Corp B and frame corp C.
 2) cause a catastrophic failure at corp C's important remote strategic facility (like an orbital station) with the only evidence being that it was Corp B.
 3) send the runners on a "quiet op" against corp A, betray them mid-run and try to kill them all with a disproportionate security response.  Have the security specialist at Corp B or C tip off the runners of the set-up.
 4) Corp B or C hires runners to deal with the original Johnson.
 5) Corp B or C debriefs the runners, one way or another, to find out how they accomplished their runs.

Campaign over.  Fixer introduces new Johnson.

[DarknessofRane]

Have it end in a double cross, Corp A sends them on the "Impossible Mission of Doom" but have Johnson show up and save them at the last minute. Then he sends them on a mission of revenge at the executive who ordered the mission, then have it come out in the wash that the executive was an innocent man and they just advanced 'Johnsons' career.

[Spooky]

Well, I suppose I should mention that the corps in play all have seats on the corporate council. Kinda hard to get to the leadership when it lives in an orbital. Also team has yet to figure out who corp a is, and they seem to not be quite aware of the VLH of doom they are slowly sliding under....

Ahh, the wailing to come.... 

[Shaidar]

The Corp Council in Orbit are only representatives of their Corp's leadership and not the leaders themselves.  Most Board Members, CEOs, VPs, & Department Heads are all planet-side.

[McGuffin]

Forget about CEOs of large corporations. Focus on major research staffers, the recent math wiz kid and extract them (from Corp B to C or vice versa).
Stealing valuable data about the newest pet project of major players within the corp is always provocative.
Even more so, would be forging and implanting compromising data, then "leaking" stuff like that to media pawns.
Giving your runner's actions the personal touch: Going after relatives (spouses, kids, ect.) of middle and high up Execs will certainly make them respond outside their usual cost-benefit scheme.

All about escalation. 

[JimmyCrisis]

Well, I suppose I should mention that the corps in play all have seats on the corporate council. Kinda hard to get to the leadership when it lives in an orbital. Also team has yet to figure out who corp a is, and they seem to not be quite aware of the VLH of doom they are slowly sliding under....

Ahh, the wailing to come.... 

There are always regional managers and delegators.  If you cut the chain, it'll cause chaos until someone repairs it.  In this case, the assassination/kidnapping should involve regional & local management and take place at an time when corp C is making an in-road somewhere (especially if the local leadership of corp C is 'nudged' in that direction), and afford them a significant advantage against corp B.  The objective is to "freeze" leadership's ability to act, causing company B to take a holding pattern.  This will look like a pretty major escalation.  A disproportionate retaliation (sabotaging an orbital station, power plant, or other "regional" vital structure owned by corp C) should nudge significant resources from each corp to bear against eachother.  Megacorporations are so large that they would never be in "total war" with another megacorporation.  There may certainly be regional warfare, however, and attacks on vital parts of infrastructure.  This should be a highly lucrative setup.

[farfromnice]

go in a factory of Corp B/C and play with the spec of a product causing a massif recall when the product go on the shelf

and I love this one, my players got to play it:
Johnson present himself with an associate, the associate ask the player to play with stupid thing in the office of Corp X. You have to put a crayon there and this plant must go at 3 meters east of the third bureau from the second door, paint this wall red, etc.

so the associate is a geomancer and is playing with the Qi of the office which would play on the productivity of the work slave. If your Corp C is wuxing or Shiawase it will be perfect because the other corp don't necessarily have an initiate geomancer on hand so they will have to buy the services of one from corp C maybe the Johnson's associate

[The Wyrm Ouroboros]

See any version of Dashiell Hammett's Red Harvest - whether in movies such as Kurosawa's Yojimbo, Clint Eastwood in A Fistful of Dollars, or Bruce Willis in Last Man Standing, or books such as the original or (IMO the best for your purposes, as it's expanded into a team instead of being just an individual that's involved) David Drake's excellent The Sharp End.