  We consider a last passage percolation model in dimension $1+1$ with
potential given by the product of a spatial i.i.d. potential with symmetric
bounded distribution and an independent i.i.d. in time sequence of signs. We
assume that the density of the spatial potential near the edge of its support
behaves as a power, with exponent $\kappa>-1$. We investigate the linear growth
rate of the actions of optimal point-to-point lazy random walk paths as a
function of the path slope and describe the structure of the resulting shape
function. It has a corner at $0$ and, although its restriction to positive
slopes cannot be linear, we prove that it has a flat edge near $0$ if
$\kappa>0$.
  For optimal point-to-line paths, we study their actions and locations of
favorable edges that the paths tends to reach and stay at. Under an additional
assumption on the time it takes for the optimal path to reach the favorable
location, we prove that appropriately normalized actions converge to a limiting
distribution that can be viewed as a counterpart of the Tracy-Widom law. Since
the scaling exponent and the limiting distribution depend only on the parameter
$\kappa$, our results provide a description of a new universality class.
