For example, A Crown rarity card has a 5% chance of appearing in every slot of a Rare Pack compared to standard packs, where the 0.053% pull rate for a Crown rarity applies only to the final slot
Pull rate from Regular Packs: 2.27% The estimated pull rate for Rowlet (Celestial Guardians) from a Regular Pack is approximately 2.27%, meaning you might need to open around 45 Regular Packs to obtain it
*Drools* (Retreat Cost is a big deal when Gust of Wind runs amuck
On the other hand, there are some non-Niv decks in older formats that could probably use Jegantha, the Wellspring, the question is whether starting with a random 5/5 for five in hand is the best use of a sideboard slot
Using creatures such as Mnemonic Wall, Archaeomancer, and Ardent Elementalist, you can cast one of these flicker spells on the recursion creature to be able to get your flicker spell back instantly