I would say Hylian Shield is the most useful shield on a FOnewm (Increases resistance by EFR 25 ETH 32 EDK 35, also boosts grantz by 100%, rafoie 75% and razonde 60%. Red ring is useful when you're just meleeing for the ata boost. Lastly, merges can be helpful. Especially resta merge. Hylian shield only drops during the triforce event in September, typically from gal gryffon on certain section IDs, red ring drops from dark falz, you can find it in the drop chart. The merges you can make with amplifiers and barriers and sometimes they drop easily during events (like easter).Also anti dark ring is helpful for avoiding instantly being killed by megid easily since it raises your EDK by 60. Drops from dark falz with viridia on ultimate.