Special Summons your banished Rock-type monster to the field.
This card is co-existent with the monster Special Summoned. If the card is removed from the field, the monster is destroyed; If the monster is destroyed, this card is destroyed as well.
This is a very good card to make use of your banished Rock-type monster by bringing them back to the field.
You can also include Premature Return as an alternative to your deck that is built around banishing/returning.
To utilize Release from Stone’s effect, you should have Rock-type monsters that are consistently being banished. Gaia Plate the Earth Giant requires you to banish 2 Rock-type monsters to Special Summon, and on top of that, you are required to banish 1 Rock-type monster from your Graveyard every Standby Phase, as a cost. Delta the Magnet Warrior is able to banish 3 “Magnet Warrior” monsters from the Graveyard to Special Summon Valkyrion the Magna Warrior. Megarock Dragon’s Special Summoning condition allows you to banish as many Rock-type monsters as possible, from your graveyard.
Do they have to have been in play first??? Some of the Gem-Knight fusion monsters say, "First, summon the is card to the field with..." Does "first" mean they have to have been in play to use this card?
You can send Lady Knight Brilliant Diamond to the GY from your extra deck and then immediately banish her w Gem-Knight Fusion. But even if you have Freed From Stone set, you cannot summon Lady Kn
Some monsters need to be properly Summoned first before they can be revived. Fusions, Synchros and Ritual Monsters work this way, as do monsters that say so (Cards that say "Must first be Special Summoned by..." or "This card can only be Special Summoned by..."). In the case of the Gem-Knight Fusions, this means being Fusion Summoned, which means you can't revive one Summoned by Brilliant Diamond.
How come the card doesn't destroy itself when the monster is destroyed like it says in the description?
If you tribute it or banish it, it hasn't been "destroyed" technically.
It also seems like there are certain situations where you can't use the card to summon certain Gem-Knight monsters.
It doesn't seem like you can send your big fusion monsters to the Graveyard with Lady Lapis Lazuli, banish them to return Gem-Knight Fusion and then immediately special summon them with Release From Stone.