Ichor

Ichor is a crafting material dropped by Ichor Stickers in the Hardmode Underground Crimson. It is the Crimson counterpart to the Corruption's Cursed Flame.

Tips
Ichor does not burn up in lava, so pouring lava on Ichor Stickers is a possible way to collect Ichor.

Trivia

 * Ichor, in Greek mythology, is the golden ethereal fluid that flows in the blood of gods and immortals, as said in the item's description. It also means a discharge from wound or ulcer, which fits more to the disgusting theme of Crimson, but the description of ichor specifies that it was meant as the gods' blood.
 * It can be pronounced "aye-car", "aye-kur", or "ick-er".