Gonna bring these 2 points back up since nobody has been talking about them. Victini seems like an S-Rank mon thanks to its sheer power. It has 2 ridiculously powerful STABs in Blue flare and V-create as well as a powerful coverage move in bolt strike. Base 100 speed is good in UU and it allows victini to outpace some dangerous threats like heracross and darmanitan. It is also quite bulky as 100/100/100 defenses are nothing to sneeze at. It has quite a few flaws, such as being weak to entry hazards and poor typing, but its pros outwiegh them.