Not particularly challenging, but fun! Double Nuke or Spikes + Laser are all it takes to clear most waves. You can generally go infinite with the extra wave bombs. I think I only had to re-do a level once: level 2 or 3, and that was only because I didn't understand the chest/submarine star mechanics.
Would love to see a method (shift+click?) to lock a "known" tile. Oh, and for those who seem to be mistaken: This is not a Simon Tatham game, at least not originally. His implementation is based off one made by Pavils Jurjans. It's even in the credits on SGTatham's puzzle pack, if you look.
2-slice 1878% - had to get 100% on 1, 5, 6, 9-15, and 17-20. Level 7 at 62% too. This video helped a lot for 14: http://www.youtube.com/watch?v=zcZF91HINfA
Just got the Impossible badge, and every other achievement in the game too. Took about a week, but it was fun. Hints: Start with the sheriff, get max Dr Holiday, and use your shotgun the entire game. Upgrade to a shotgun with at least 4 mod slots, and add in Anti-armor, Damage, Leech, Accuracy. Get Noble/Ranger/Militia minions up to big gun 11 to give them Gravity Guns with impact and leech mods. Invest in 100 chickens or so, and 15 sisters if an ally has "Love". Taunting isn't useful anymore since monster HP now stacks. Taxes pile up fast in Hardcore, be prepared for a major funding shortage around level 40 if you don't have Accountant, Love, Breeder, et cetera.
Dear god the Exocet font makes your eyes bleed after a while. Please oh please, switch to something else. Large titles and whatnot are fine in Exocet, but reading anything beyond that is just torture.
Achievements should be awarded for surpassing their criteria. For example, in level 1, if you do it in a single shot then you do not get the achievement; you must do it again in exactly 2 shots.
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