Frox

Throw a brightbloom so you can see the mouth before it starts inhaling. If you are pulled in, you take a heavy hit and come back out with less health. A bomb flower detonates in the throat and flips the body. A brightbloom seed also stuns it, and it lights the ground for the climb. Either one is enough. Do not throw your only weapon into the mouth.

While it is stunned, climb onto the back and hit the zonaite ore with a hammer or a two-handed weapon. When the ore breaks, the Frox dies and drops zonaite along with fangs, fingernails and guts. If you are too slow, it stands and inhales again. Get off before it shakes. Little Frox use the same mouth, with less ore and less health, and they are the ones that ambush you between lightroots.

Zonaite from the back becomes crystallized charges at a forge in an abandoned mine, and those charges are how you expand the energy cell. A Frox is a faster zonaite stop than chipping every rock wall. Fangs and nails are fuse materials. Guts go into elixirs. Large ones are worth a bomb flower. Little ones are worth a brightbloom seed and a spare hammer.

They only walk the Depths, so a surface Blood Moon does not put one in a field you already cleared up top. Underground they return to the same basins. Mark a large one next to a lightroot. Arrive with a brightbloom in hand, not on the ground behind you, or the inhale starts while you are still blind.