A couple of things:
- Almost all extended tests are gone. Instead of an extended test taking a bunch of action phases to hack a commlink, you now make one or more individual tests to gain "marks" on the commlink, and different numbers of marks allow you to make different kinds of actions. This allows hackers to be a part of the game, including during combat and such, rather than a separate minigame that bores the rest of your players to tears.
- There are a few different ways to get marks, and each way has "side effects" for your net hits, either Matrix damage or free hits as if from a Matrix Perception check. This lets you think strategically about what actions to use, rather than simply "oh I'm hacking, time to roll the single dice pool I use for every hacking action and wait for the GM to tell me I win."
- Cybercombat is no longer simply a thing you use when you get caught, but an integrated part of your hacking strategy. You can attack a node and drop its dice pool to make it easier to hack on later actions.
- The way hacking devices linked to commlinks has been both improved and clarified.
- The dice pools are now done with ATTR+Skill like every other test in the game, and the Limit for your hits is what's based on your deck's attributes.
- The addition of GOD means that even hacking easier commlinks carries some risk, since every hit on every defense test against your hacks gets added to your cumulative "overwatch score" (whether they successfully defend or not); once that score hits 40, the Man converges on you, dealing hefty damage and dumping your ass offline. Your overwatch score can be reset by rebooting, but that also resets any marks you've gained, so deciding how long to stay in control of the devices you've 0wned is a risk/reward decision as well.