Considering that "modify" is just a new batching term and we've only got one set's worth of modify payoff cards, it's not a shock that a precon based around this loose "theme" would be half-baked, which Upgrades Unleashed unfortunately is
Imagine this in one of those insane Druid decks
We can sacrifice The Hollow Sentinel to the Throne, proliferating and immediately making a new Hollow Sentinel, which means we can proliferate each turn for 0 mana
Finding that elusive spell you need in Master Duels many packs could take hours, so youll be glad to hear that the game has a card crafting system
This is an exciting card for sure, and it gives players loads of possibilities for building different Commander decks
Then there's a final card that will only go to winners - presumably meaning that only four copies will be made in total