From the newest Scarlet & Violet chase cards to random commons from Base Set 2, the inventory is staggering
Medusa's last ability resolves before the spell that caused it to trigger
(To proliferate, choose any number of permanents and/or players, then give each another counter of each kind already there.) The value of X is determined only once, as Tromell's last ability resolves
Second, based on the rumored reprinting time frame of Modern Horizons 2 and Wizards mentioning off-handedly that Lord of the Rings will leave Magic Arena in 2025, it's pretty safe to assume that whatever deal Wizards worked out for Lord of the Rings allows them to do new print runs of the set for the next two years, which would make the release similar to Modern Horizons 2 , at least as far as reprint potential
You could sacrifice a card like, Sentinel's Eyes to bring back a control powerhouse like the oppressive Overwhelming Splendor as early as turn four to shut down your opponent's strategies until it's removed