Great game! Solid mechanics that lends itself for many interesting twists in a sequel! :) meetreen_games - is it by design that you don't have Credits and studio name in the game itself? :) Maybe timer is a bit of an issue for me. Number of moves taken is much more natural IMO for a puzzle.
I am the dev/coder of this game (kingdotcom is our beloved sponsor). Thanks lot for your comments! Will take them for the sequel: will make sure zen mode is more epic, maybe will add action mode, score popus will not block your view. I especially liked the comment about adding goals beyond score objectives for the missions.
Thanks for feedback guys! Not doing upgrades/shop was not an easy decision, but wanted to have 1 finished game, rather than 1 unfinished project. ;) Your comment is well taken though - if I do the sequel, that would be N1 thing to add.