Overview
2015 Koenigsegg One:1 appears on the official Forza Horizon 6 car list as a S2 Class (hypercar tier) entry in the base roster. This page focuses on what the car actually means for everyday players: how it tends to drive in its class, where it fits inside Forza Horizon 6's Japan setting, how to think about a starting tune, and which other roster entries it naturally compares against.
If you found this page while searching for a single Koenigsegg model in Forza Horizon 6, you are in the right place. Everything below is built around the official list fields (year, class, pack, manufacturer) plus plain-language player notes. We do not invent horsepower numbers, hidden upgrade paths, or unlock guarantees that the official list has not confirmed.
Background and Forza Horizon 6 context
The One:1 had a 1:1 power-to-weight ratio: 1,360 hp from the twin-turbo V8 and 1,360 kg curb weight. Just six were built, all sold before announcement, and the car set a 0-300-0 km/h record of 17.95 seconds at Suzuka in 2015 before being eclipsed by the Agera RS in 2017. On the official Forza Horizon 6 car list this 2015 Koenigsegg entry sits in the S2 Class (hypercar tier) bracket inside the base roster, which is the placement players come to this page expecting to confirm against the public source. Inside the same S2 Class (hypercar tier) bracket, the closest comparison roster entries for players are 2013 Ariel Atom 500 V8 and 2016 Aston Martin Vulcan, which is the S2 Class (hypercar tier) peer group this car is usually weighed against.
Driving feel in Forza Horizon 6
One:1 was the first production car with a 1:1 power-to-weight ratio (1MW = 1,360PS, 1,360kg kerb weight). Only seven were built. In S2-class events on Japan's longer straight-heavy routes the One:1 accelerates harder than any rival of the period; the active aero (1,210kg downforce at 260km/h) is the dominant chassis variable.
Where it shines
S2 class is for top-end road events, drag-style straight sections of Japanese expressways, and competitive lap-time challenges.
Tuning starting point
Tuning at S2 is where you choose between top-speed runs and lap-pace. Keep one tune for each style if you race both. Rear-wheel-drive cars want a softer rear and careful throttle on corner exit; pay attention to rear tire pressure especially on long Japan map straights.
These are general starting points only, not a guaranteed competitive setup. Forza Horizon 6 community tunes that already have hundreds of downloads are usually a faster route than building from scratch, especially if you are not sure of the car's drivetrain or aero behaviour yet.
How to get 2015 Koenigsegg One:1
This car is listed without an add-on label on the official Forza Horizon 6 source, so we treat it as part of the base roster. Forza Horizon 6 launches on May 19, 2026, and before that date the public Autoshow may not surface every base-roster car yet — players asking 'how do I get this car, it is not in the Autoshow?' on Reddit or the Forza forums usually find the answer is 'wait for launch day or a post-launch update'. After launch, base-roster cars are normally available through credits in the Autoshow, Wheelspins, Festival Playlist rewards, or the in-game showcase that introduces new vehicles.
