G-99 Breakneck is a brand new car-mount introduced in patch 11.1 Undermined. It is very unique in that it will not appear in your mount journal, but instead show up as a spell called D.R.I.V.E in your spell book. D.R.I.V.E is only usable in the Undermine zone and the experience of using it is more reminiscent of a vehicle than a traditional mount.
D.R.I.V.E Mechanics
The D.R.I.V.E vehicle has some unique mechanics to help you traverse the new undermine zone in style. While in the G-99 Breakneck you will see the vehicle interface shown in the image below.
The car has 4 abilities and a turbo bar. The first ability is Boost, which gives your vehicle a large amount of speed for a short duration, while using 33% of your Turbo bar. This ability can be modified to either increase the duration at the cost of speed, or increase the speed at the cost of duration. The Turbo meter can be refilled by either drifting (explained below) or collecting canisters around Undermine.
The second ability is Horn, which makes a honking sound. This, as far as we can tell, is just for flavour and has no real effect. If you use it too many times within a short period of time you will get the Time Out! debuff which prevents you from honking for 1 minute.
The third ability is Start Job, which will start the D.R.I.V.E shipping and handling minigame. When you start the minigame you will get a green arrow above your head pointing you in the direction of your next job. The job will usually consist of you either killing some mobs, delivering packages or collecting items. For some jobs you will remain in the car, and for some jobs you have to exit it to do the objective.
You can complete 10 jobs in a row before returning to the garage for a mandated break, which means you have to sit down and drink, using the extra action button, for 60 seconds before being able to do 10 more jobs. To stop receiving jobs click the Clock Out ability, which replaced the Start Job button.
Every hour there is a Surge Pricing event. This event increases the rewards of the D.R.I.V.E shipping and handling minigame. By completing jobs you help fill the shipping and handling bar and can earn Tip Chests which contain Valorstones, Gold and Resonance Crystals.
The last ability simply exits the vehicle.
Drifting
The most unique mechanic to D.R.I.V.E is drifting. Drifting is achieved by turning and then pressing the spacebar. Drifting will cause your vehicle to turn more sharply, but also slide sideways, like a real life car on ice. You generally have to drift in every turn, as the turning on the D.R.I.V.E is otherwise very wide.
There is a learning curve to the D.R.I.V.E car, but with a bit of practice it is definitely the fastest way to get around Undermine. If you are looking to further customize your D.R.I.V.E experience you can check out our D.R.I.V.E unlocks guide.