Earthbound Geoglyph

While any Level 10 monsters are on the field, neither player can target this card with card effects, also it cannot be destroyed by card effects. You can treat 1 Synchro Monster as 2 Tributes for the Tribute Summon of an "Earthbound Immortal" monster. If a Synchro Monster(s) is Special Summoned (except during the Damage Step): You can add 1 "Earthbound Immortal" Spell/Trap from your Deck to your hand. You can only use this effect of "Earthbound Geoglyph" once per turn.