The veterans here have no doubt already been checking drop rates, but for those of us who either farm very casually (if at all) or who are newer to the game (welcome, recent arrivals!), here’s a quick update with helpful links for when you’re looking to raise those new LB3 Servants and with next year in mind:
(Edit: Added Nobu Avenger - thanks, @Tirpitz_007!)
Xiang Yu wants 72.
Incoming welfare Santa Quetz wants 30.
2021 Servants who also want them: Arjuna Alter, Ganesha, Musashi Summer, Kingprotea, Astolfo (Saber), Jason
There aren’t that many Giant’s Rings in the 2021 event shops, so anyone who doesn’t already have a large stockpile or who is aiming to raise more than one or two of these Servants needs to get busy. See the GP link below for drop locations ranked by AP efficiency, but choose your preferred spot based on other drops you need to determine your most overall efficient location.
Xiang Yu wants 161.
2021 Servants who will want powder: Santa Nightingale, Space Ishtar, Lakshmi Bai, Bartholomew Robers, Calamity Jane, Osakabehime (Archer), Nobunaga (Avenger)
Gunpowder isn’t bad to farm, but many Servants want it in tremendous quantities.
Reactor Core of Dawn
Xiang Yu, Yu Miaoyi, and Qin Shi Huang want 53, 36, and 60, respectively.
2021 Servants: Ashwatthama, Da Vinci (Rider), Osakabehime (Archer), Okita Souji (Assassin), Kingprotea, Space Ishtar, Europa, Nobunaga (Avenger)
Cores are worse to farm than Giant’s Rings, but significantly easier than hearts. Thankfully, the node that appears to be the most AP-efficient for cores also features bells as an added bonus! Event shops will give us some, but not enough to raise more than one core-intensive Servant comfortably.
Yu Miaoyi, Qin Shi Huang, Red Hare, and Qin Liangyu want 44, 36, 48, and 60, respectively.
2021 Servants: Li (Assassin), Murasaki, Benienma, Ganesha, Chen Gong, Hokusai (Saber), Reines, Nobunaga (Avenger)
The most AP-efficient location for bells offers no other drops of note; for almost everyone the better bet will be to farm the top drop location for cores since it also drops bells. Only farm the most efficient bell-only node if you are in a huge hurry or need no cores for the foreseeable future.