it's endless score attack match-2-or-more until you lose. the optional tutorial is full of tapping, always annoying and a sign of a lazy port, but since they didn't rename the game to click the blocks (which they should've), it's almost acceptable.
the gameplay is like this: columns of blocks appear, click clusters with the same color to make them disappear. no cascades, you decide what goes. the catch is, columns at the end get pushed off-screen by newcomers, that's when you lose a life, inevitably leading to game over, man.
each round has an increasing number of columns and lasts as long as it takes the bug on the bottom to cross the screen. columns appear every few seconds, clicking the shaman speeds up the process and might lead to bigger combos with more blocks, but also to disaster. blocks also fall randomly to mess things up. the fewer blocks left by the end of the round, the higher the score. if the score bar fills up, a bonus round happens to rack up more points. you can't die here, no gaps on the bottom, only random blocks falling from above.
settings can be brought up while playing. only separate toggles for audio, no volume settings, plus a smaller non-resizable windowed mode, a billion languages and local high score. not a list, just the last and the best, would've made sense to add profiles or player names or something for some local competition. also, an exit button, has to be mentioned.
that's pretty much it. this kind of thing entertains me for about an hour because there's no actual goal or progression, but it's fun and people more into competing with others or themselves (or just going for grindy achievements) can find longevity in it. speaking of, achievements are buggy. just start the tutorial and go back to the menu to get the ones for surviving until round 5 and 8 without losing a life.