Cards And Zones
What Does a Card Forget When It Leaves the Board?
Leaving for a non-board zone clears temporary changes. Coming back is a new object, while simply moving between board locations is different.
RiftPal explanation · Answer first
The short answer
When a card changes zones to or from a non-board zone, treat it as a new object. Clear its DamageDamage represents harm marked on a unit and stays marked until it is healed.View in Glossary , counters and temporary changes, including granted keywords and statuses. If it comes back, those old changes do not come back with it.
Simply moving from your BaseYour Base is your personal location where your units can be played and return to during the game.View in Glossary to a battlefield, or back, does not cause this reset: those locations are both on the board.
RiftPal explanation
How it works
Returning a unit to hand, putting it in the TrashA player's off-board zone for cards that are killed or discarded and spells that finish resolving, unless an effect changes their destination. Its cards are public information and their order does not matter.View in Glossary or banishing it clears its temporary changes. Even a champion returning to the Champion ZoneThe separate zone where your Chosen Champion starts the game. You can play it from there using the normal timing, costs and restrictions. It is not a location on the board.View in Glossary loses its buffs.
If a targeted unit leaves for a non-board zone and comes back before a spell on the ChainAn off-board zone that holds cards and abilities during the process of playing them. Cards and abilities on it are public information.View in Glossary resolves, that spell no longer affects it as its old target. Other instructions may still happen. Moving between Base and a battlefield is different: the unit remains the same object and can still be a legal target if it meets the spell's requirements when it resolves.
TokenA game object created by a spell or ability during play, represented by a printed token or another marker. It follows its type's rules but is not a card. After moving to a non-board zone other than the Chain, it immediately ceases to exist.View in Glossary disappear after moving to a non-board zone other than the Chain. They do not stay in your hand or Trash to return later.
Some effects explicitly use information across a change. A spell or ability that moves an object as its cost or effect can check its characteristics before that move. Replace has a special “swap back” procedure that gives the returning card the replacing token's current effects and statuses. Those are specific exceptions, not the normal result of leaving and returning.
In practice
Example
A unit has a buff and 2 damage marked on it. An effect returns it to your hand: remove the buff and damage. If you later play that card again, it does not retain either. Merely moving the unit from a battlefield to your Base would not clear them for this reason.