Thrall is a Grimoire card from the original Destiny (Destiny 1), found under Enemies → Hive. Grimoire cards held most of the game's lore and were read on Bungie.net and in the companion app, not in the game itself.
Card text
Feral and fearless, Thrall are a plague upon the battlefield.
Their swarming, twisted frames are driven by unfettered rage. Of all the terrors born of the Hive's vile will, they are the basest.
Their swarming, twisted frames are driven by unfettered rage. Of all the terrors born of the Hive's vile will, they are the basest.
Grimoire text written by Bungie, shown as it appears in the Destiny 1 game files.