  We study the universal behavior associated with a Relativistic Boltzmann
Transport (RBT) approach with the full collision integral in 0+1D conformal
systems. We show that all momentum moments of the distribution function exhibit
universal behavior. Furthermore, the RBT approach allows to calculate the full
distribution function, showing that an attractor behavior is present in both
the longitudinal and transverse momentum dependence. We compare our results to
the far-from-equilibrium attractors determined with other approaches, such as
kinetic theory in Relaxation Time Approximation (RTA) and relativistic
hydrodynamic theories, both in their viscous (DNMR) an anisotropic (aHydro)
formulations, finding a very similar evolution, but an even faster
thermalization in RBT for higher order moments. For the first time, we extended
this analysis also to study the attractor behavior under a
temperature-dependent viscosity $\eta/s(T)$, accounting also for the rapid
increase toward the hadronic phase. We find that a partial breaking of the
scaling behavior with respect to $\tau/\tau_{eq}$ emerges only at $T \approx
T_c$ generating a transient deviation from attractors; interestingly this in
realistic finite systems may occur around the freeze-out dynamics. Finally, we
investigate for the first time results beyond the boost-invariant picture,
finding that also in such a case the system evolves toward the universal
attractor. In particular, we present the forward and pull-back attractors at
different space-time rapidities including rapidity regions where initially the
distribution function is even vanishing.
