Checked it all 8 cores used on 65%+ the moment I run the game.
It seems odd that it would load the CPU that much, but also it suggests that you do have a cooling issue. Unless the CPU is pegged at 90%+ for extended amounts of time, a decent cooler / thermal paste should keep the CPU well under 100c.
You may want to take off your cooler, reapply paste and then remount, then see if the temps are doing well.
Also, there's plenty of CPU Burn-In tests out there, to verify that your cooling is working well. Under normal conditions, loading the CPU should not get the CPU up/over 100c unless there is a cooling issue.
Give Prime95 a try. I can run my CPU at 100% load for extended periods with this testing tool and my cooling will keep it in the 80c max, and it only gets there after the cooling gets saturated. It begins at around 60c and slowly climbs after the cooling apparatus gets soaked with heat.
Check out this page: https://www.tomshardware.com/reviews/stress-test-cpu-pc-guide,5461-2.html