Cactus Game Design Message Boards

The increase on Joy and other similar cards is just a regular ongoing ability that follows the same rules as other ongoing abilities. If Joy is negated or removed from the Hero, the increase ceases to function.

Same with the granting of CBN? Once discarded it ceases to work?

When an ability is either CBN or not when it activates so if the Hero's ability activates while Joy is on it, the Hero's ability will be CBN indefinitely even if Joy is removed. However, if Joy is removed and the Hero deactivates, next time it activates (Without Joy) it will not be CBN.

So I play joy on the music leader and then my opponent discards joy from my music leader. My  opponents next turn he lays down Moses. Is the music leader who no longer (but once had) joy on him is now negated. Correct?

If you put Music Leader in territory then place Joy on him, ML doesn't actually immediately become CBN since when his ability first activated, he did not have the CBN modifier from Joy. ML would need to reactivate while Joy was placed by entering battle for it actually to do anything so ML is actually negated in this example even if Joy was still present.

Ok so same seneraio. Music leader has joy on him. He wins and still has joy. My opponent discards joy. On his next turn he lays down Moses. Is ML now negate or deactivated because joy is no longer present? Or does he need to leave play to lose his ability ?

ML is in territory and had Joy when he entered territory.  Therefore, ML was CBN when he activated.

As long as ML stays in territory, he stays CBN, because he was CBN when he activated.