Leyline of the Wastes

Colorless spells and nonmana abilities of colorless permanents have Assist (Another player can pay any amount of the spell’s or ability's generic mana cost).

Whenever a player pays for a spell or ability
they don’t control, that player may create a treasure token. If they do, exile all other abilities of Leylines.

"...and their artificial leylines often had unintended consequences."