  We report the development of a 4-color simultaneous camera for the 1.52~m
Telescopio Carlos S\'anchez (TCS) in the Teide Observatory, Canaries, Spain.
The new instrument, named MuSCAT2, has a capability of 4-color simultaneous
imaging in $g$ (400--550 nm), $r$ (550--700 nm), $i$ (700--820 nm), and $z_s$
(820--920 nm) bands. MuSCAT2 equips four 1024$\times$1024 pixel CCDs, having a
field of view of 7.4$\times$7.4 arcmin$^2$ with a pixel scale of 0.44 arcsec
per pixel. The principal purpose of MuSCAT2 is to perform high-precision
multi-color exoplanet transit photometry. We have demonstrated photometric
precisions of 0.057%, 0.050%, 0.060%, and 0.076% as root-mean-square residuals
of 60~s binning in $g$, $r$, $i$ and $z_s$ bands, respectively, for a G0 V star
WASP-12 ($V=11.57\pm0.16$). MuSCAT2 has started science operations since
January 2018, with over 250 telescope nights per year. MuSCAT2 is expected to
become a reference tool for exoplanet transit observations, and will
substantially contribute to the follow-up of the TESS and PLATO space missions.
