To test whether we can generate better poses, we decided to make predictions using AutoDock Vina and DOCK 6 along with HYBRID in Stage 1b. HYBRID uses pre-generated conformations with Omega and places them in the binding pocket in different positions and orientations to have similar 3D conformation as the reference crystallographic ligand. On the other hand, AutoDock Vina uses a stochastic global search algorithm , while DOCK 6 uses a more systematic search using the 'anchor-and-grow' algorithm . Both of them do not need any reference binding pose to perform the search.