Minion
A guard posted beside a boss: a Rime Witch with Hrym, a Stone Sentinel with Thrym. A minion outlives its master, so you have to cut it down yourself, and the fight isn't clear until you do.
In detail
A minion spawns as part of a fixed boss warband, outlives the boss, and its kill counts toward clearing the fight. A summon is the other half of the split: conjured mid-fight, and it dies with its summoner. Charms that key off Common enemies count minions as real kills.
More in glossary
From the current development build. Content and balance may change before release. This public reference includes discoveries and does not reflect your personal unlocks.