On paper, it seems pretty balanced and self-restricting, for sure there won't be any oppressive card with this ability
However, there are tradeoffs too - spreading yourself across more than one store can be time-consuming and fiddly, plus this dilutes your ability to build up a good seller reputation
If they don't, put those cards into your graveyard and draw five cards
The Ancient Copper Dragon was arguably the biggest hit to pull from the Commander Legends: Battle for Baldur's Gate set, which has translated to it being one of the most valuable reprints as part of Magic: The Gathering 's Final Fantasy set
What affects the value of Rillaboom
(1) Send 1 monster from your hand or field to the GY, then target 1 of your Level 1 monsters that is banished or in your GY, except the sent monster