Тонущий маяк

Jorbs

Glowwater Potion is very strong, but early in the run it can be quite difficult to make good use of. Unless you have some cards which gain energy, drawing 10 doesn't actually let you do all that much. In contrast, Fresnel Lens is great to get early in the run, since you still have the entire rest of the run to get offered defensive cards which take advantage of it. I usually take Fresnel Lens here unless I have good energy gain and/or need a potion for an upcoming difficult fight.

Baalorlord

You have to give up a lot of max hp to get the lens, but it's quite worth it. Compare 13 hp to 2 hp per block card you play in an act, and you can see that the Lens easily makes up for the health deficit once you add a few blocks. The Lens improves all block generated by a card, so cards that block multiple times like Dodge and Roll or Toric Toughness benefit multiple times from the enchantment. You can get the Fresnel Lens to enchant your defends if you remove and then re-add them with the Pael's Tooth blessing. Since cards can only have one enchantment, the Lens can be a downside if you end up wanting a different enchantment on your block cards.