Some effects care about who did the killing (e.g. Crown of the Victor). Only units can get credit for a kill. Determine credit for a kill when a minion dies (i.e. marked for death), in priority order (highest first): Did a unit just strike or deal damage with a special ability? Did a unit just resolve a Magic spell they cast? Did a unit just activate or trigger an ability, including abilities granted by artifacts? If any of the above are true, in priority order, then that unit is the killer. Examples: A Vile Imp resolves its Genesis ability, dealing two damage to a minion. The Imp gets credit for killing that minion under condition 1. An Avatar casts Bury, forcefully burrowing a minion so it dies underground since that minion doesn't have burrowing. The minion dies there and the Avatar gets kill credit under condition 2. Asmodeus breaks stealth, activating his ability, and destroying a minion. He gets credit under condition 3. If a unit is tapped to pay for an ability (e.g. Payload Trebuchet), they count as 'activating' the artifact's ability for purposes of kill credit. The killer must be a unit, but multiple units can share credit for a kill, if they both share the same priority. For example, Grapple Shot will only give credit to the ally who strikes, not the spellcaster, since priority 1 is higher. If two units defend against a single attack, both defenders could get credit for the kill. Note that passive abilities and other ongoing effects are not included in kill credit. Only activated and triggered abilities are included at priority 3.