  We study the (hydro-)dynamics of multi-species driven by alignment. What
distinguishes the different species is the protocol of their interaction with
the rest of the crowd: the collective motion is described by different
communication kernels, $\phi_{\alpha\beta}$, between the crowds in species
$\alpha$ and $\beta$. We show that flocking of the overall crowd emerges
provided the communication array between species forms a connected graph. In
particular, the crowd within each species need not interact with its own kind,
i.e., $\phi_{\alpha\alpha}=0$; different species which are engaged in such
`game' of alignment require a connecting path for propagation of information
which will lead to the flocking of overall crowd. The same methodology applies
to multi-species aggregation dynamics governed by first-order alignment:
connectivity implies concentration around an emerging consensus.
