I've spent a lot of time trying to understand the possible treasure combination that would be best. Since in 100% you have to go to the big diamond cutscenes, and getting treasures I believe is faster than going through the dialogue with the character in the cutscene, we opt to go for the treasure chest.

The Treasures (These are the permanent upgrade versions of the Magical Treats) : Magic Book, Speed Potion, Rainbow Potion, Running Shoes, Magic Feather, Magic Ring, 2 Live up.

What I am unsure of: How the treasure choice works. It feels like a 50/50 decision to the player that is also hidden behind a 50/50 chance of the item ACTUALLY being in the chest on that frame when you press a. I'm gonna try and get a hold of some frame by frame software and see if I can get the same treasure on the same frame or if it is dependent on something else entirely. If there was a way to either manipulate the RNG factor (if it is RNG) or find some way to get specific treasures, I'm almost certain time could be shaved off of each subsequent world by selecting a specific selection of treasures at the end of each world.

What I am Sure of:

1. Any treasure is better than the running shoes treasure. This is because of the way item progression works when the user starts the game or dies. When Bub dies, he loses his shoes, and the two potions hes collected along the way as well as any non Big Diamond Treasure. Then, every third enemy he kills, he gets a magical treat. First the running shoes, then the speed potion, then the rainbow potion. For this reason, getting the running shoes treasure can be fatal to a run if a life is lost. You waste time having to recollect the running shoes, and running quickly when lacking the speed potion and rainbow potion can really mess up the pathing for certain levels. (World 3 and 5 comes to mind)

2. The two best treasures are the Magic Feather and the Magic Book.

• The Magic Feather: The magic feather summons a fairy that circles Bub to protect him from harm. While this does stop enemies from hurting Bub, it can be used offensively to generate the small diamonds. A hit with the fairy will cause an enemy to transform into a small diamond as if they were hit by a Rainbow Smash attack.
• The Magic Book: By far, in my opinion, the best item in this game for speed running. It can let Bub infinitely jump. This can be used to skip the long, empty vertical climbing segments of World 5, and help with the traversal of world 7 and 8 as well. Also, being able to not rely on platforms can allow for some quicker kills against Fangs, Choppy, and world 7 boss.

3. Magic Ring can be useful to tank specific areas of upcoming worlds that would save time through routing. You only get one hit (if I'm not mistaken), and I'm not sure if you are invincible for much long after, so it might be useful for damage boosting through certain boards that are particularly difficult. This could be used later in the run after other treasures were acquired first.

4. After the Magic Feather and Magic book, I think the potions are the best best items. I believe Speed potion has more benefits from the get go, but these are really only useful after a death. It could be in the future, a intentional death is take to use the invulnerability is used to get a quick kill on a boss (I'm thinking maybe could be used on the world 8 boss to get to phase 2 faster) but you would need all three magical treat treasures to make this possible. (With the other two, that leaves 2 worlds to get anything of personal preference before this fight) Again, this is only theorycrafting if its possible to control which treasure appears in the chest.

After doing a bit of research, I'm pretty confident that selecting treasures within the Big Emerald cut scene is not determined by how many frames have progressed. I could be wrong, but after running through the last couple hours selecting a treasure chest on the same frame (total frames of the game passed) I'm getting mixed results. Sometimes I get a treasure, and other times the chest is empty.

It could be that it has something to do with what frame the boss is defeated on, as I had different boss fight patterns during my tests.

And then there is the chance that this is all random and can not be controlled by any factors.