Stupid gameplay example: https://www.youtube.com/watch?v=wcD_bCeV_y4&t=177s&index=2&list=PLHWQUfOX13x2kQmuR-oJJFKhM6bAMhGqX
Plonk down Lastlight Druid immediately prior to casting Hall of Lost Kings, or empowering a Pillar of Amar several times. (Make sure you put down the Pillar before the Druid, or transform the Druid to prevent your Pillar from being transformed.)