true when MonsterType equals MonsterTypeBoss (2). Derived at load time from the table row. Confirmed by recon on the Ancient Purifier run: attr-10 → MonsterTable[33301].MonsterType == 2.
Numeric monster classification (0=Monster, 1=Elite, 2=Boss). Mirrors EMonsterType from the zproto enum. MonsterRank is empty for all table rows and must not be used for classification — use this field instead.