Gavin Verhey from Wizards of the Coast explains Heroes of the Realm 3.0 3.1 3.2 Comment by u/Wizards_Drew on r/magicTCG on Reddit Outside of a unlisted rule for the Commander format that the original recipient of a Heroes of the Realm card is allowed to use it
Classics like Charizard and Mewtwo, were part of the original Pokmon TCG lineup
The wording allows you to either generate a second copy of the same creature from your deck, or grab a completely unrelated creature which happens to share the same total stats
If youre not winning all at once, Zahur will ensure you win eventually
Sword Sparks: In case of literal spark, seen in the artwork of Tryce
The cards have no monetary value, and you can't trade or sell them, but its a fantastic, risk-free way to satisfy the urge to open packs, learn the cards in a new set, or just pass the time