While any player controls a Grandwalker Nexus, this card in your hand is Cost 4.
[LV1][LV2][LV3] (Start of Your Attack Step) You can deploy a Nexus card from your hand by paying one cost.
[LV2][LV3] (When Attacks) Once per turn, by exhausting a Nexus/Grandwalker Nexus you control, this Spirit refreshes. When a Blue Grandwalker Nexus is exhausted by this effect, put one core from the Void to this Spirit.