unblock it! - an uncoventional tetromino puzzle

So, another tetromino puzzle, huh? What could possible be done differently in this decades old concept. But wait before moving on to the next title, give 'unblock it!' a try! The goal of this tetromino spin-off is to clear the blocks of the evergrowing tower by placing tetrominos over it. Drag the green tetrominos from the right onto the game field and drop it wherever it is best to clear the dark violet blocks. Gold, silver or bronze coins will boost your scores. Be careful, if the tower ever reaches top, the game is over. Oh, and there are power boosters in case you are stuck!