Clash of the Eikons

Removing lore counters won't cause a previous chapter ability to trigger. If lore counters are removed from a Saga, the appropriate chapter abilities will trigger again when the Saga receives more lore counters.

Putting a lore counter on a Saga will usually cause its next chapter ability to trigger. If it already has a number of lore counters on it that's greater than or equal to its final chapter number, however, no chapter abilities trigger.