The best gaming routers seem to be the Netgear Nighthawk x6 or x8 models. Both of these models made top router lists at both PC Mag and PC Gamer, and both perform astoundingly well. However, both are also north of $250.
If your budget is in the $100-$200 range, multiple ASUS RT models feature great reviews with strong performance. PC Gamer specifically highlights the ASUS RT AC88U as the best all around gaming router, although it's price tag is in the $300 range. It's cheaper cousins still pack plenty of punch.
There are routers that are priced less than $100, but their performance for gaming applications leaves much to be desired.