Best Free Replacement for Malwarebytes?

Windows 7 x64 Home Premium; i5 3570K; 8GB DDR3; GTX970

I am running Emsisoft Internet Security (annual subscription) on my 5 machines and have been very happy with it. Until tonight, I also ran Malwarebytes Anti-Malware ("MBAM") free version, to run occasionally as a "second line of defense" or "second opinion."

Like most people, I try to keep my software up to date, especially my anti-malware software, which I understand needs periodic malware signature updates to remain effective in the face of changing threat environments. However, on my last MBAM update, I got a version that is not content to nag me about purchasing the paid version but in addition sends "push ads" to my desktop, interrupting whatever I'm doing, throwing me out of games I'm playing, etc. In other words, it acts like Windows 10. Unacceptable.

Since this is the very reason I refuse to downgrade to Windows 10, I uninstalled MBAM and I'm now looking for recommendations for a "second opinion" on-demand free anti-malware tool for Windows 7 that is content to be my mistress and not my wife.

I would appreciate any recommendations. Thanks.