This if hilarious. But maybe some dev got a bonus for inventing this.
If you are F2P, even if you immensely try and finish all 50 tower floors (and waste a ton of artifacts by the way) there is no matemathical chance for a free token (shuriken) pull during this months event.
For finishing 50 floors all you can get is 98 or 99 tokens XD
For me it is just another indicator to #nospend a dime on this game. Congrats to devs for this ‘backup’ with a F.