Neu in ReaxFF 2018 Stress Stain ReaxFF has been included in the AMS driver as one of the engines, which means that all tasks that can be performed with the AMS driver are also available for ReaxFF. However, not all tasks available in the classic ReaxFF standalone program have already been ported to AMS, so in the 2018 release of the Amsterdam Modeling Suite, the standalone ReaxFF program and the ReaxFF engine coexist. This manual mostly describes the standalone ReaxFF program. For documentation on how to use ReaxFF in AMS, see the special page on ReaxFF as an AMS engine as well as the AMS driver manual. Besides the addition of ReaxFF as an AMS engine, the standalone ReaxFF 2018 program has been extended with the following features: The CMA-ES method for force-field parameter optimization; Initial implementation of the collective variable-driven hyperdynamics (CVHD); Bond-boost method for accelerating specified reactions; Heat pump and HEX NEMD methods to study thermal conductivity; Temperature profile along the cell coordinate vectors, which is very useful in combination with NEMD; Per atom stress tensor can be computed with ReaxFF; Local temperature (averaged across atoms within given distance); Analysis of surface reactions; On-the-fly analysis of reaction events; Elastic wall restraint (a must-have when applying external electric field); Performance improvements and bug-fixes.