Broken Advancement Question

I’m not sure if I’m reading the rules right - when time clock fills (for the first time) it says the undead gain an ability. Sofar I read this in singular, that one of the undead gains one ability,the other does not.

Reading the reward of the first special mission in Duresh Forest I think I might have gotten it wrong.

So when time is filled does one Broken gain an ability or both?


Page 185: “Broken gain a new ability whenever a “Time” clock on the Commander’s sheet fills. Think about what abilities they’ll get so that you can hint at the horrific research being done by the Broken to learn such things.”