This Nexus can only be affected by effects that specify "Grandwalker Nexus". Core can only be placed on this Nexus through the effect of "Core Charge" or effects that specify "Grandwalker Nexus", also, core on this Nexus can not be moved except by effects that specify "Grandwalker Nexus".
Core Charge: ("Ancient Dragon"/"Worldswalker"/"Avatar" & Cost 3 or higher)" ◆When you Summon/Advent a target Spirit, put one core from the void onto this Nexus. ◆When this Nexus is deployed, if you do not control a Nexus with the same card name as this card, send the top three cards of your deck to the trash. For each target card among them, place one core from the void onto this Nexus.
Grand Skill: 4 [LV1][LV2] (Your Main Step) - (Once per turn, send four core from this Nexus to the Void) Draw two cards.
Grand Field [LV2] (Your Attack Step) Add a Red Symbol to all your "Sieg" Spirits.