  We study collisions of Gaussian mass-density blobs in a holographic plasma,
using a large $D$ effective theory, as a model for holographic shockwave
collisions. The simplicity of the effective theory allows us to perform the
first 4+1 collisions in Einstein-Maxwell theory, which are dual to collisions
of matter with non-zero baryonic number. We explore several collision scenarios
with different blob shapes, impact parameters and charge values and find that
collisions with impact parameter below the transverse width of the blobs are
equivalent under rescaling. We also observe that charge weakly affects the rest
of quantities. Finally, we study the entropy generated during collisions, both
by charge diffusion and viscous dissipation. Multiple stages of linear entropy
growth are identified, whose rates are not independent of the initial
conditions.
