From my own experience, there's a few things to consider when comparing a laptop to a desktop.
- Case Size (Airflow)
Laptops are naturally compact, whereas a desktop has a lot more breathing room. Laptops, especially recent models, tend to have everything soldered to the motherboard as well, in an effort to save even more space. Every nano-meter counts nowadays. Because of this, laptops won't have as much airflow in the case, nor will they have larger heatsinks, as Jeff Zeitlin mentioned.
- Fans (Airflow)
My desktop keeps itself at a cool ~35°C while idling, and this is partly due to fan configurations. Two intake fans and one exhaust fan keep cooler air moving in, while pushing out hot air from the back. The more fans, the better. In the case of a laptop, typically only the CPU and, depending on the card, the GPU, have fans. There is no room for a proper intake and exhaust set up, so things will generally be hotter.
- Specifics to your situation
Black Ops (depending on the version) and Overwatch are not what I would consider graphically intense games. They can be, but with the settings turned down a bit to favor performance, your laptop probably won't generate much heat. I can't say as much for League having never played it, but I imagine you've got some settings turned up higher on it, which can lead to a higher heat graphics card.
85°C isn't good by any means, but it isn't necessarily bad. You would do well to worry once you start hitting 90°C, as you're getting closer to temperatures that can damage your card and internal components.
Perhaps try taking the case off of your laptop and cleaning it out with some compressed air to get rid of dust. Dust is an excellent heat conductor, and unfortunately finds ways to worm into our electronics.