Practice Room. Free to Play (F2P) no mints, no money plants strategy that earns most of its points from killing all 3 Cardio Zombies (1.125 million on them alone). All Plant Food is used to refresh Squash. This has only scored this well in Practice mode, as I've been unable to beat Cardio at all in actual Battlez. Yet again there is a huge disparity between Practice and actual: as you can see, Cardio is very easily killed in Practice, in only 10-11 seconds for the first 2! Also, I've heard zombie health scales up with the tier of the league you're in, so zombies would have the most health in Jade. So for Jade League, this setup will not kill Cardios; it *might* in lower leagues but I don't know.
I based this on TheRealGamer's strategy, replacing his level 7 Bowling Bulb (mine is lower level) with my Dusk Lobber. So thanks goes to him. His plants do kill all Cardios in actual Battlez, apparently in Silver League. Since league seems to have a significant impact on effectiveness of strategies, I'll start including it in my video descriptions.
Plants vs. Zombies 2: It's About Time Statistics For TheMaruMari
TheMaruMari presently has 379,741 views for Plants vs. Zombies 2: It's About Time across 1,808 videos, with the game making up over 4 days of published video on his channel. This is 48.70% of the total watchable video for Plants vs. Zombies 2: It's About Time on TheMaruMari's YouTube channel.