Excellent game! You've shown me that I'm an absolute sucker for these grid-based puzzles. Especially once it got to the end, the puzzles took freaking ages to complete. Fairly certain I spent over an hour and a half on the last one alone. However, the feeling of joy when the numbers of a row greyed out was spectacular. Keep more like this coming, and you'll keep my attention for sure.
Playing through it, and I've noticed four things that would be nice to have: 1) Queuing for units; press the button multiple times, it makes that many units in a row. 2) Actual stats for the units; being able to compare one to the other and tell which is better numerically would help. 3) Active unit counts; the units are all too small and clustered to get an accurate count of how many there are of each type, and keeping x amount of y unit becomes difficult when half of them die and you don't know which half it was. 4) Small glitch in the Defend AI; whenever the units killed someone, they immediately ran back to the castle before attacking the next enemy. This usually ended in them taking more damage than necessary in the process. If these were fixed, this game would be even more great than it already is.
The only suggestion I'd make is an auto-spawn option for each unit. With this, it would automatically spawn the certain unit whenever you have sufficient materials and it's off cooldown. Having to constantly spam 1 to summon my rats gets a bit tiring after a few dozen levels.
Wow, this game is fun. I can't remember the last game that brought such a smile to my face and kept it there the entire time I was playing it. It's just the right amount of challenge without being annoying. 5-starred, love it. Only suggestion would be stats for the weapons, or maybe just a description of what they do.
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