tl;dr: nice style, some logic and usability issues.
I'm just going through the "unlocking" levels so I might review again later - if I get to it and don't loose my will to play first.
- the style: the paper box theme is well executed throughout the menus and maps, IMO.
- destroyed units are very nicely done! (they burn/explode, remain as coal-like skeletons (until they are impacted too much and vanish, i.e. shot down planes crash so hard into the ground that they disappear, except sometimes and then you get a nice burning wreck on the ground :-)))
- if you select a tower you can on the left choose the tower view. it's nice watching. Just wish your money counter and some kind of "furthest enemy progress percentage" were visible in case you are just waiting for the next cash update or don't want to risk the leading enemy getting too far even though you are watching from a tower not trained on them.
- You are being told that towers can't shoot through trees. What they don't tell you is that the towers are stupid. Just plain stupid. They will shoot at trees when there are other targets in plain sight. They will shoot at single targets when waiting a fraction of a second would make it re-appear in plain sight. They will shoot at other towers as if they were trees. Maybe with all tower types unlocked this will be less of an issue.
Maybe this is intended to increase the "toybox" and wind-up toys feeling but it's very frustrating when compared to other TD games where one even can choose preferred enemy types, ranges/positions, etc.
- Cannons that shoot ground and air target will happily be locked on a heavily armored, slow, long-winding pathed vehicle while a fast, light aircraft can fly right over it and disappear into the box. Obviously air-only towers are supposed to help in such a situation, but with the tree-stupidity one might need more ground-targetting towers -and therefore occupy slots - than is good for air-cover. That said, the flak seems to be nicely powerful if upgraded :-)
- Connected with the previous issue: you only get very few and FIXED tower placement points. That means you have to think very carefully where to place which type and even more ANTICIPATE how they will interact on ANY target of any level (AND MIXES thereof) to make "sure" you don't hit only trees because your towers got stuck in a bad timing loop and misses every window of opportunity just to fire at the next tree.
- You can't place or upgrade towers while paused, that means you (and your hardware!) better be fast enough!
and the HORRID:
- scrolling: You can only scroll by cursor keys and they produce mega-leaps instead of managable shifts so half of the time you end up not seeing the view you want but half of it. (I play it in lowest resolution if that makes any difference). Simple standard scrolling with mouse at borders or dragging the map with middle mouse button hold would fix this!
Also, sometimes the view scrolls away without user input, maybe due to arriving vehicles or selection of towers (that are fully in view, btw!) and messes everything up even more.
Also, because of the scroll issues, make sure that you look at the whole map zoomed out to not miss any available tower placement spots!