I finally finished it! & then got to lvl 34. Very pleased. But I still think there are many major improvements that this game needs. I won't come back to play it again, I just wanted to know I could do it. & speaking as someone who's finished it, I still say it's mostly down to luck. Of course you need to have some sense, but it is a luck-based game. My only advice is to always try to think ahead a few moves before placing any tiles, or at least do so when you're down to the last 3 or 4 spaces in the ring.
I got to level 24, filled the ring everywhere except 1 place which required 2 terras. Such a tile never even came up this round & I had no bombs or things to change it to terras so I automatically couldn't do it. It's a shame that the few flaws this game have spoil it so much. Like everyone's saying - we need saves & to not just die after the first fail.
 "Gravitee 2"){kind=icon}
 "Ghostscape"){kind=icon}
 "Alien Abduction II"){kind=icon}
 "The Nerds Quiz"){kind=icon}
 "IndestructoTank! AE"){kind=icon}
 "Particles"){kind=icon}
 "Perfect Balance"){kind=icon}
 "ZunderFury"){kind=icon}
 "Smileys-War"){kind=icon}
 "Globetrotter XL"){kind=icon}
 "Ring Pass Not"){kind=icon}