Add a whole new dimension of gameplay
Collecting a Conclusion Dack's Duplicate | Illustration by Karl Kopinski Its better than not getting anything for these duplicate cards, and the introduction of duplicate protection indeed improved MTGA's economy but it still doesnt feel reciprocal
What are the Doctor Who Commander decks
Siege still has a lot of potential, but given the rules text, I'd guess effects that don't involve transformation, but a direct punishment for not protecting it, would need a new subtype
After all, it is basically a 4/3 that gains two life when it enters the battlefield and then has the option to gain us two life a turn if things line up
For just two mana you get a solid removal spell, blowing up any creature with a power three or less