This list has been truncated:
SDM, LMNM, RN, RHDM, NDM, TN, SMM, LD, RDM,...
Supply exactly one missing member - there are a few to choose from.
SLVR
as silver is a metallic element, fulfilling two criteria, one of which is failed by CRBN, and the other of which would be failed by BRNZ or BRSS.
blackjack
flooble's webmaster puzzle