Its standard dimensions of 66.591 mm make it ideal for everyday play, not just tournaments
Because of the way Kroxa and Kunoros' ability resolves, you can sacrifice it in response to the reanimation clause, sacrificing it to the Altar, to mill six cards and then exile five of them to return Kroxa and Kunoros to play, triggering its ability again in an infinite loop
Its just
Selesnya decks are typically all about life gain and steadily growing creatures through the use of counters, and while the counter aspect is present on T'Challa, the life gain aspect is currently missing
If you played Return to Ravnica Booster Draft, you already know just how powerful the Pack is
On the flip side, the decks you need cheap removal most against are the ones with the most things this will hit