  We introduce a new simulation and analysis paradigm for Imaging Atmospheric
Cherenkov Telescope (IACT) arrays, simulating the actual observation conditions
as well as individual telescope configuration for each observation unit.
Compared to existing frameworks, where simulations are usually generated using
pre-defined settings, this run-wise simulation approach implies more realistic
simulations and hence reduced systematic uncertainties. The computational
effort of this dedicated simulation concept is notably independent of the
amount of different observation configurations but just scales linearly with
observation time. This corresponds to a large advantage for increasingly
complex current and future IACT arrays where the size of the phase space makes
it computationally unfeasible to generate simulations that reach the
requirements regarding systematics using the classical simulation scheme.
