I finished the game this morning

Enjoyed the game overall. I'll put my "final thoughts" (as if Im Jerry Springer or something) here.
The story was cool and I like the part near the end when they get home to the wife and kids! The music is really good, the mood at the end was great. It has some nice moral messages in their too. But I thought it was a shame how on the last level you climb to the top but then as soon as you get the scroll it goes to the credits and dramatic music, felt underwhelming. It would have been much better if it was a bigger more visually appealing scroll (it looks the same as all the others) and instead of having the number above it, it says 'end (for now)' or something. And then perhaps flappy ninja could hold it up looking at it and you could fake a zooming out effect. Before it then goes to the credits. Something like that anyway, it just felt very underwhelming as a last scene goes.
The turtle character in the game is the best, the way he helps you out (with the player pushing him in to the armored soldiers) is a really cool mechanic, I was a bit disappointed he hadnt rocked up earlier in the game! I think the game could do with a couple more really good mechanics like that, as the same soldiers all the time can start to feel linear.
When you pause the game, the music should pause too.
I realised right near the end that you can go to the pause menu and click on 'Restart Scene' and it doesnt cause your 'fails' counter to rise. During the scenes where you have to get all scrolls in a certain time period if I had a poor start at getting first few scrolls I would run to the nearest spikes so I could restart, this ticked up my fails counter every time by 1 (and I did it a lot!), when I should have just gone to the menu and restarted the scene. Some players will realise this, others wont, it would be more fair if when you restart the scene it still causes the fails counter to rise by 1.
A bug I experienced was on level 33 when for some reason Khan just disappeared. I have attached a screenshot, nothing happened so I had to use the pause menu to restart the scene.
Another thing with the ads is it would be good if the scene didnt reload until the ad had been closed. What happens is the scene begins and I start to move and then a split second later the ad kicks in, it is quite annoying so it would be much better if the new scene didnt begin until the ad had been closed/viewed/etc.
And one final thing, for polishing the design up I think going for more consistency would help. For example if you look at the icon, as in the google play store, the writing is a smooth font, but the ninja is pixel art style and the scrolls are had to tell exactly what are style they are. But when in the game the menu has the smooth font at the top, but then the text on the buttons appears to be pixel. I know its important to have contrast but at least sticking to one art style (pixel definitely seems best for it) I think would benefit the final quality feel of it.
Hope that helps anyway, its a fun game, so with more work I reckon you could make it better and better