The NVIDIA Shield TV is a 4K HDR streaming box and a gaming console rolled into one, and you can get it for $170 for Black Friday, down from $200. That includes three free months of YouTube Red, a $30 value.
Just note that for gaming, your options here are a selection of Android games, streaming games from your PC with a GeForce graphics card, or subscribing to GeForce Now for $8 per month, which gives you streaming access to an array of AAA titles.