Location: School of Fish
Depth: 218

Solution to Go At It!

by Iolanthe Chronis and Davie Rolnick

Answer: ISABEL

Each of the clues leads to a two-letter answer.

Microchip (IC)
Superman's Krypton surname (EL)
Sumerian sky-god (AN)
Prince William's mom (DI)
One hour earlier than ET (CT)
The fatal quantity of a poison (LD)

24, above Mo (CR)
WHO parent organization (UN)
Switzerland, from Latin (CH)
Kinetic or static coefficient (MU)
Palmetto State (SC)
Novelist John ____ Carré (LE)

Spin doctor's specialty (PR)
Where the weak shall be eaten (EC)
Talking horse's surname (ED)
"It" in Germany (ES)
Subject of 8.02 (EM)

Combining the answers gives three new clues:

ICELANDIC TLD (IS)
CRUNCH MUSCLE (AB)
PRECEDES EM (EL)

The answer is ISABEL.