"

From the most useful to the least useful
• S: Alchemist's Ring / Compound 33
  
• A: Blighted Crow / Blighted Rat / Compound 21 / Iridescent Blight Tag
  
• B: Canker Thorn / Foxglove / Umbra Salts / Plague Bile / Vigo's journal
  
• C: Rose Tonic / Pustula Dust / Shredded Notes
  
• D: Compound 7 / Soul Chemical / Summoning Stone
  
• E: Chipped Monocle / Adrenaline Vial / Placebo Tablet

Note: B tier addons or above are recommended, C tier addons have a tiny worth if you combine them with other one (for example: Shredded Notes + Iridescent Blight Tag). This is not a surprise to see the famous Alchemist's Ring as the best Blight's addon, also Compound 33 as well and just imagine using both at the same time ;)
D tier addons just for meme builds... meanwhile E tier addons... don't use them!"