"Dropped by nothing." does that mean the item is not in MS Legends?

Welcome to MapleLegends! Don't worry about not knowing something, everyone starts as a beginner. As far as I know, there's no a complete guide on all non-dropped items in the game. I'd list some I can think of right now:

1. iTCG Equipments: Not available in ML.
2. Miscellaneous event items: Check out Discontinued/collectable items guide by Kargo. Most of them are unlikely to return.
3. Scrolls: Some scrolls are only obtainable from Gachapon. Here is a list of Gachapon rewards.
4. Quest items: Try looking it up on hidden-street or find the related quest guide via search engines (don't use the search box on forum, it probably won't help you find the desired result).
5. Maple Equipments: Only available during anniversary events, or buying them from other players.

By the way, check out this thread to get a boost for your maple journey if you haven't. Happy mapling

 

Balanced fury are found in the cwk exchange or by crafting
Exchange and craft NPC are unlocked via a series of quests in NLC there is a guide here https://forum.maplelegends.com/index.php?threads/guide-crimsonwood-exchange-pre-quests.41199/

I havent found a detailed list of what can be rewarded from the different exchanges but the NPC will tell you what you can win. They are tweaked a bit for ML so outside sources like hidden-streets.net wont display accurate rewards