Necessary Combinations:

Shop - Apple + Banana Guess the Words (mini-game) - Potato + Lemon (The list of word definitions is located in the guide) Sale in the Shop - Banana + Cabbage Magic Mushrooms - Cherry + Avocado

The fruit combos for level skips (in no particular order):

Grass Land - Apple + Avocado Temple Land - Banana + Mango Lunar Land - Orange + Cherry Wood Land - Potato + Potato Mine Land - Potato + Cherry Snow Land - Potato + Avocado Dead Land - Cabbage + Pear Desert Land - Mango + Onion

Other spells that are useful/necessary:

Slow Time - Banana + Mushroom 2x Time Icons - Mango + Mango