Karn Liberated design?

Gideon

+3: Discard all cards that can be discarded from your hand.Those cards gain the deciphered emblem. Draw 2 cards

-3: Exile the first card without mana from your opponents hand. Then: Exile an opposing support card at random. Those cards gain the Deciphered emblem.

-15 Destroy all the creatures and all the gems. Then: Return all nonspell cards with the deciphered emblem from each players exile to the battlefield under your control. Those cards lose the deciphered emblem.

I don’t see any evidence when using the 1st and 2nd ability that cards are getting the “deciphered emblem”. What does the Deciphered emblem look like? More importantly the first ability dumps cards with the deciphered emblem into your graveyard and there is no way to get them back because the 3rd ability only affects exile. Please redesign this card.