  We present a detailed chemical abundance analysis of the brightest star in
the ultra-faint dwarf (UFD) galaxy candidate Cetus II from high-resolution
Magellan/MIKE spectra. For this star, DES J011740.53-173053, abundances or
upper limits of 18 elements from Carbon to Europium are derived. Its chemical
abundances generally follow those of other UFD galaxy stars, with a slight
enhancement of the alpha-elements (Mg, Si, and Ca) and low neutron-capture
element (Sr, Ba, Eu) abundances supporting the classification of Cetus II as a
likely UFD. The star exhibits lower Sc, Ti, and V abundances than Milky Way
(MW) halo stars with similar metallicity. This signature is consistent with
yields from a supernova (SN) originating from a star with a mass of ~11.2 solar
masses. In addition, the star has a Potassium abundance of [K/Fe] = 0.81 which
is somewhat higher than the K abundances of MW halo stars with similar
metallicity, a signature which is also present in a number of UFD galaxies. A
comparison including globular clusters (GC) and stellar stream stars suggests
that high K is a specific characteristic for some UFD galaxy stars and can thus
be used to help classify objects as UFD galaxies.
