At its heart, Ortus Novae is designed to be flexible. It's designed to work with whatever models, tokens or units you have to bring to the table, but it also has associated miniatures, so this page exists to give some expanded guidance on how die classes work in Ortus Novae.
Using the picture above as an example, we can see a collection of units about to engage in furious battle. The most prominent one is probably the fighter jet flying over the ruined building. Due to the size of the unit, I classed it as a d8, on par with the four VN crawler-style drones in the far back and center. The fighter jet is also classed as a special unit (flying + thrusters) which gives it additional bonuses and additional cost.
You may also notice that the four VN crawler drones I mentioned in the prior paragraph have four different turret-top styles. The one to the far left has two cannons, the one in the middle has a missile launcher array, and to the right of that, we can see a drone with a single cannon and a drone with a dish. These pieces can be used as stand-ins for any drones with any abilities, but when I built them, I had the following in mind: all VN crawler drones are classed as d8's. The one with two turrets is an Elite Unit (2d8), the one with the missile array is an Artillery unit, the one with the dish is an HSU unit, and the one with just a single cannon is just an ordinary unit with no modifiers.
In front of them, you can see two flying drones (proxies grabbed from a game by Dutch Mogul of Ill Gotten Games.) Due to the size of these units, I classed them as d6s (they're about the same size as the cars below, which would all be d6s as well) and gave them the Flying special trait because they have flight bases.
Speaking of the cars below, you may notice that one of them has an especially large cannon on it. Classing these units, I considered them all to be ordinary d6 units except the one with the cannon, which is a d6 with the Artillery trait. Behind the fighter jet, you may also notice a white bus. Typically I class Analog war bus units as D8s.
Another pair of proxies in this picture are the hovertanks (originally interceptors by the aforementioned Dutch Mogul) which I class as d10 units. Tanks are heavy combat machinery, and should always be classed at the upper end. After all, in a match between a d6 Analog War Car and a d10 VN Hovertank, chances are the dice will fall in favor of the tank.
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