  We report the discovery of a $(1.0 \pm 0.28) \times 10^{10}$ M$_\odot$
Supermassive Black Hole (BH) at the centre of NGC 708, the Brightest Cluster
Galaxy of Abell 262. Such high BH masses are very rare and allow to investigate
BH - host galaxy scaling relations at the high mass end, which in turn provide
hints about the (co)evolution of such systems. NGC~708 is found to be an
outlier in all the canonical scaling relations except for those linking the BH
mass to the core properties. The galaxy mass-to-light ratio points to a Kroupa
IMF rather than Salpeter, with this finding confirmed using photometry in two
different bands. We perform this analysis using our novel triaxial
Schwarzschild code to integrate orbits in a 5-dimensional space, using a
semi-parametric deprojected light density to build the potential and
non-parametric Line-of-Sight Velocity Distributions (LOSVDs) derived from
long-slit spectra recently acquired at Large Binocular Telescope (LBT) to
exploit the full information in the kinematic. We find that the galaxy geometry
changes as a function of the radius going from prolate, nearly spherical in the
central regions to triaxial at large radii, highlighting the need to go beyond
constant shape profiles. Our analysis is only the second of its kind and will
systematically be used in the future to hunt Supermassive Black Holes in giant
ellipticals.
