Beat game in a couple of days with left hand glaive, right hand missles and body lasers. All on tier 6, with relevant research upgrades to about 7 or 8. No need for the super-expensive powers. The final boss is relatively easy (level 15 boss is more annoying with those black balls that push you around) once you've got decent weapons. Just stick in the centre bottom and stay there until he's dead. The blop magnet research is annoying, since it seems to push blops away beyond a certain distance.
The game over page could at least record your score. But this game has pretty much zero features and is about as interesting as watching grass grow... Oh.
There is a bug that occasionally puts your turrets off the top of the screen when you try to place them on a location where a turret was destroyed in the previous wave.
After level four or five, this games gets significantly easier. As others have noted, the turning point is the flamethrower. If you can make it to that, then things get much better.
How to get Obsessive achievement. Although you cannot manually repair walls during the assault phase, you can repair your keep (blockhouse) as long as you have it selected when you hit "Begin the Assault". Particularly once you have free repairs from another achievement, then you can win an entire skirmish with your keep alone by continually repairing it as it is attacked.
Once you have Overprotective, it's actually quite difficult to get Obsessive, since any lightly damaged walls are already repaired and don't need your help. This leaves you with only heavily damaged walls to fix, which are much rarer.
French pros and cons. Although French canon strength is listed as a pro, all canon do the same damage (i.e. instant kill). Since they also all have the same range, the only difference between the three different tiers is firing speed. Also, French con listed is that tier 3 soldiers have nothing special, yet they have pretty awesome damage compared to other troops. This is a big plus, not a con.
@SpaceCatStudios: A few more bugs to fix. The French tier 3 awards do not reduce the cost of the Garde. Though the cost changes in the right-hand panel from 95 to 85 to 72, 95 gold is still deducted in any case. Also, despite what the tool tip says, caltrops don't slow troops and all canon have the same range.
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I've added some little features ;) Not so much, but always something.