Random Restarts on iMac Late 2013 w/ OS 10.15.7

A couple weeks ago my mac started randomly restarting while playing SC2. There is no “your mac must shut down because of an error” before it shuts down and no “your mac restarted because of an error” on boot up. There’s no text indicating a kernel panic. The error code is -128 when checking previous shutdown causes in Terminal.

The restart occurs at different times when using SC2. Sometimes it will happen when I go video card settings, sometimes during the loading of a co-op mission, sometimes in the middle of a co-op mission.

The restarts appearing does not appear to have followed any SC2 or Mac OS software update, and I don’t use the system for anything but playing SC2 and watching movies.

I have been researching the issue and have already tried the following items:
-renaming the mac in System Preferences → Sharing
-reinstalling SC2
-reinstalling Mac OS X
-booting from recovery drive and running disk utility repair
-this system has an NVIDIA 780M, so the issues with Radeon do not apply

I do notice something interesting in my logs:
Jul 3 20:41:19 iMac Battle.net[3849]: objc[3849]: Class BlizzardCoreURLConnectionDelegate is implemented in both /Applications/Battle.net.app/Contents/MacOS/Battle.net (0x1052fa4d8) and /Users/admin/Library/Application Support/Battle.net/Versions/Battle.net.13560/battle.net-core.framework/battle.net-core (0x10a7e91a0). One of the two will be used. Which one is undefined.

I see this three times in my log before each crash. Would love some guidance on what to do here.

mac sucks get yourself a real computer. Build your own.