The effect is worded as follows:
- Nether Unleash: 3 [LV1][LV2][LV3] (When Attacks) Send three cores from the opposing Field to the Reserve. For each Spirit depleted by this effect, send an opposing Life to the Reserve. Then, by sending three cores from any Purple Grandwalker Nexus(es) you control to the Trash, send up to 5 cores from the opposing Reserve to the Trash.
An effect which simultaneously does removal, life burn and scorched earth, but unlike average Unleash effects, the player doesn't get any core they can instantly make use of. The deck's main mechanic is having Spirits whose Level 1 core cost is 0, so while the cores aren't necessary for levelling up Spirits, they could be used by the player to counter an attacking opponent on the following turn, were the opponent to endure by ending the attack step or by using Diamond Wall-type effects.