Overall) - Distant Melody AND Kindred Discovery Check out this kindred caring twosome
[20] On each player's turn, following a set phase order, they draw a card, tap their lands and other permanents as necessary to gain mana to cast spells, engage their creatures in a single attack round against their opponent who may use their own creatures to block the attack, and then complete other actions with any remaining mana
Griselbrand is banned for other reasons, of course, but the ability to draw that many more cards is what sets it apart in Commander
Commander deck, the price can be expected to decrease towards a more stable average
Too Similar - When you have a leader who is very powerful, and their deck is the same each time, it can get boring to play against them
If a token or a card that isn't represented by a transforming double-faced card becomes a copy of a Siege, it can't be cast as its triggered ability resolves