  The impact of a hydrogel sphere onto a granular target results in both the
deformation of the sphere and the formation of a prominent topographic feature
known as impact crater on the granular surface. We investigate the crater
formation and scaling, together with the spreading diameter and post-impact
dynamics of the spheres by performing a series of experiments, varying the
Young's modulus $Y$ and impact speed $U_{0}$ of the hydrogel spheres, and the
packing fraction and grain size of the granular target. We determine how the
crater diameter and depth depend on $Y$ and find the data to be consistent with
those from earlier experiments using droplets and hard spheres. Most
specifically, we find that the crater diameter data are consistent with a power
law, where the power exponent changes more sharply when $Y$ becomes less than
$200$ Pa. Next, we introduce an estimate for the portion of the impact kinetic
energy that is stored in elastic energy during impact, and thus correct the
energy that remains available for crater formation. Subsequently, we determine
the deformation of the hydrogel sphere and find that the normalized spreading
diameter data are well collapsed introducing an equivalent velocity from an
energy balance of the the initial kinetic energy against surface and elastic
energy. Finally, we observe that under certain intermediate values for the
Young's modulus and impact velocities, the particles rebound from the impact
crater. We determine the phase diagram and explain our findings from a
comparison of the elastocapillary spreading time and the impact duration.
