Shatter
Each turnTurnDuring a battle round, each unit on the battle map takes a turn. Some abilities are limited to a certain number of uses per turn; that limit is reset at the start of each unit's turn., the first time this unit is engagedEngageAdventurers may engage multiple times per turn but are limited by the dice they can roll and fatigue they can gain. You may perform a move action before or after you perform an engage action, but not both. by an adventurerAdventurerEach character created by a player is an Adventurer. Each adventurer is a party member. who is not overtaxingOvertaxWhen you trigger an item's standard ability, you may also choose to trigger its overtax ability (but cannot trigger the overtax ability without triggering the item's standard ability). If you do, after the engage and both item abilities are resolved, that item must be discarded. a 
WeaponWeapon items provide advantages in battle, often interacting with skills. Each has a standard ability that is resolved as part of an adventurer's engage. However, each Weapon also has a secondary, overtax keyword ability that can be triggered in addition to the item's standard ability when using the Weapon to engage., that adventurer must discardDiscardCards are discarded to a separate discard stack. Dice return to the supply. Defeated enemy chips go to a defeated enemy stack. Other chips go to the appropriate draw bag or supply. a weapon from a ready slotItemsAdventurers can gain useful items along their way. Each item card takes up 1 space in an adventurer's inventory, whether it is in a ready slot or the pack area. There are 2 types of item cards, common and legendary. after the engage.
Does Shatter still trigger even if the enemy is defeated during the engage?
Yes, Shatter will still trigger even if the enemy is defeated. "...after the engage" is to clarify that you can still use the weapon and it's abilities for the engage action.
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