Donten ni Warau Gaiden: Ketsubetsu, Yamainu no Chikai

Anime you can only find (or used to only find) on Amazon, I'm going to add anime you could technically watch on HIDIVE (because Sentai has the licenses, they get to share some series). Note that I'm not adding shows which could be considered "old" because they weren't released as amazon-only initially, so no Gamba or Takarajima. Also no 'Ishida to Asakura', you can't fool us with that 2021 date Amazon, it came out in 2013. Not adding shows which are on other streaming platforms in the West (If I were to consider them I'd add a note), so no Asia streams or programming in other regions. Of course, if I get something wrong put it in the comments, this is to keep track of anime on Amazon but don't expect this to be the most "official" list because of expected region differences. Note also that some can be found on Funimation but due to Crunchyroll's merge I'm still unsure about adding them, I mostly get the streaming info from LiveChart although I've noticed it also misses some streams like 'Unbreakable Machine Doll' or the new 'Initial D Legend' movies which are available with Prime. As a side note, Amazon owns the right to many sequels but either has the original on Prime (But I consider other streaming platforms so no 'Psycho-Pass 1') or under a paywall.

Edit 2023: Because of the many licenses gone to HIDIVE this list is trying to compile what were Amazon Originals, I'm slowly working my way to knowing exactly which series fit these criteria, such as Vinland Saga which started as an Amazon original but then went on to be in Crunchyroll and Netflix, if a series is in the two of the biggest anime streaming platform Funimation and Crunchyroll (although they're basically the same now they still work as different platforms) they're not admitted here however if on one of the two then it's fine, why? because at that point being an alternative platform doesn't cut it when a series is on two of the more popular anime streaming services.

Part 2: https://myanimelist.net/stacks/994

Calling all anime fans!

Prepare to be enthralled as we reveal a secret vault of mesmerizing anime movies. In this extraordinary series, I present Part 01 of the Hidden Gems collection. Brace yourself for an immersive experience, filled with thrilling action, heartfelt stories, and unforgettable characters. These hidden treasures are waiting to be discovered by you. Don't miss this chance to dive into the captivating anime movie universe. Get ready for a wild ride of excitement and wonder!

Anime series that covers all of its original source they're based on, with some notes.

Part 1: https://myanimelist.net/stacks/16812
Part 3: https://myanimelist.net/stacks/20122
Part 4: https://myanimelist.net/stacks/20258
Part 5: https://myanimelist.net/stacks/20709
Part 6: https://myanimelist.net/stacks/20940
Part 7: https://myanimelist.net/stacks/21451
Part 8: https://myanimelist.net/stacks/21523
Part 9: https://myanimelist.net/stacks/29835
Part 10: https://myanimelist.net/stacks/35847
Part 11: https://myanimelist.net/stacks/39870
Part 12: https://myanimelist.net/stacks/41719
Part 13: https://myanimelist.net/stacks/42460

Anime whose characters are voiced by Nakamura Yuuichi and Sakurai Takahiro