20 bonus skills?

[DokEnkephalin]

The skill planner's options for bonus skill points go up to 20. I've gotten 10 of those, where do I find the final 10? Were they quest rewards, or am I thinking of a different game?

[Bryan]

Global did indeed offer up to +20. The premium +1 skill point consumable had a cap of 10 and was untradeable, while the regular version was tradeable. (The wiki does not list a cap of 10 for the latter, but it should have one.)
Now what Steam did with those I wouldn't know. I imagine both are somehow available - and if not, mods should easily make it so.