Slitherine

I'd like to overstrength units when there is no slot cost, but I can't find any file that gives a comprehensive (or any) list of the overstrength vs slot information. Obviously I can click each unit when purchasing/upgrading to get the information, but I'm wondering if there's some place where all the information is available. Or is there some formula that is applied?

(I've not been able to find it in Units.csv or Rules.json.)

For every 5 OS, your slot cost is doubled, let's make this clear first.
So for 1 slot units, you can OS it to +3 before having an increaase in slot cost. For 2 slot units, you can OS it to +1. For anything above, OS will at least cost you 1 more slot. If a unit's slot cost is reduced by commander traits like Panzer General or Infantry General, the cost is calculated with the exact number after reduction, i.e. a normal infantry units cost 3 so any OS increases slot cost, but with Infantry General it becomes 2 slot and can be OSed to +1 for free.

Virgil has pretty much said it: when you do +5 OS, you double the final slot cost.
Everything between is linear interpolation.

If you want a formula:
Y = final slot cost
X = base slot cost
OS = value of overstrength

Y = X + (2*OS*X*/10) => rounded to nearest value

Ex: applied to a 1 core slot unit (X = 1) with 2 OS (strength = 12)
Y = 1 + (2*2*1/10) = 1,4 => rounded to 1

With 3 OS (strength = 13)
Y = 1 + (2*3*1/10) = 1,6 => rounded to 2


Ex: applied to a 6 core slot unit (X = 6) with 4 OS (strength = 14)
Y = 6 + (2*4*6/10) = 10,8 => rounded to 11

Etc...

Thanks for the replies.