Butterfly Triplets

I explain how the butterfly triplets work. Thanks to bad_boot for explaining all of this info to me (https://www.youtube.com/channel/UC280....

Summary: There are 2 types of butterfly triplets: In the first type, there's 1 butterfly that transforms into a 1-up and 2 butterflies that don't transform into anything. In the second type, there's 1 butterfly that transforms into a 1-up and 2 butterflies that transform into bombs. Every butterfly has a subtype. In the case without bombs, the initial butterfly has subtype 4, and the two butterflies that spawn have subtypes 1 and 2. In the case with bombs, the initial butterfly has subtype 0, and the two butterflies that spawn have subtypes 1 and 2. These subtypes are used for determining which of the 3 butterflies will be the one that transforms into a 1-up. Specifically, when the initial butterfly turns visible, a random number is chosen from 0, 1, and 2, and the butterfly with that subtype will transform into a 1-up. This programming leads to a bug where in the case without bombs, if the random number is 0, then no butterfly will transform into a 1-up. This bug is expected to happen 1/3 of the time for butterfly triplets without bombs.