Thank you che1997, your medium badge guide works great.. I tried the same method on extreme mode.. strangely it works perfectly up until 142nd wave, then everything falls apart.. it's like the enemies got 10x stronger in just one wave. Anyways, something should be done about the lag.
You were right, partially. It seems to be chrome issue. I just tried on Firefox, and it works fine, no lag. I checked the processes on firefox, the plugin-container process for firefox also uses 12-15% more CPU when hovering, but there is no lag.
I couldn't record a video, but here are two screenshots showing high resource consumption when hovering over a cell.. https://imgur.com/a/YYWO2LJ
And, I think this sudden increase is the reason behind the lag.
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