this is almost impossible without power-ups, unless your a tetris god that can make tetrises and t-spins every second. instead im here to tell you the best power-ups to use and strategy. the below solution only uses 2 effective power-ups. before i list the recommended power-ups and the finisher, i have a score of 1,1105 and can consistently score above 400k. i consider myself average tetris player, and with my strategy even a beginner can master this achievement. without making this solution too long im just gonna keep it simple.
-ok so this might sound crazy. start off with the first tetris, then tap the screen as fast as you can to build the grid near the top. this will make a mess, then start to clear lines at the top of the screen. some times the mess you just created can turn into a deadly cascade destroyer. you only want to make this mess a couple of times though. then just start clearing the messy board, and you should start to see an increase in your score. in some cases, you dont even need the finisher :)