Actually you try to avoid LMK from killing Viper. One of those things to do would be to try and install Viper as a system app, to make it harder for LMK to kill it.
Even as system app, the process can still be killed when you clear background apps.
There is an app which uses the Xposed framework that allows the process to be "resident", which keeps the process in memory and it will not be affected by LMK.
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