SenorDeebs says:
Question- can I spend 4xp to pick another ‘trick’ from the Jack list of tier 1 abilities?
Not trying to step on GM's toes, but it looks like yes, per the rules you can. Page 128 in "Discovery" has a section on character advancement. There are 4 steps to complete before moving on to Tier II, all of which cost 4xp:
- Adding 4 points total do divide between your stat pools
- Increasing an Edge by 1
- Increasing your Effort by 1
- Puchasing a stat (or, like Emmett did, buy your way out of inability into a regular ability (still not trained yet).
At the bottom, there's a section called "Other Options":
"Players can also spend 4 XP to purchase other special options. Selecting any of these options counts as purchasing one of the four steps necessary to advance to the next tier."
One of the options in that list is this:
"If you’re a Jack, select a new trick of the trade. The trick must be from your tier or a lower tier."