I finally got it, this requires an "Empower Jace X" effect, where X is 10. There are three (and a half) ways to achieve this:
- Activate the [+1]-ability on Jace, Reality Sculptor with 10 islands in play.
- Attack with a Repurposed Enforcer with 10 creatures in play (under your control).
- Resolve Overwrite the Multiverse with 10 total creatures in play.

I guess Violent Echoes could work too, if you have enough effects that boost (noncombat) damage to do 10 excess damage, but that seems like a stretch.
(Edit: I guess a Twinflame Tyrant would do the trick if you were to hit a creature/planeswalker with no more than 2 toughness/loyalty. The Rollercrusher Ride would work too, provided you have Delerium)

I also used doubling season and it did not work.

Same here, i got to 31 in a game and over 10 in several others and the achievement did not get completed.

same here! I have got jace to over 20 in one match and over 10 in multiple other matches playing on standard and it will not give me the achieve. its the last one i need for the title and getting upset....

I used Jace's Machinations with a Doubling Season on my side of the battlefield and added 16 counters to my Jace token. It didn't work. I assume you must not control the token before the effect takes place e_e

I've had the same issue. I have gotten him to over 10 several times.

you need to get him to 10 or more in a single activation. The text on the achievement is poorly worded.

I had exact same issue (log attached). Sacrificed whole match to get him 10 and no achivement...