For easy mode at least (in games like these), the easiest ways is to outmaneuver the computer (more moves/sec is a good way to measure this). A few more tips: never take an even or battle where you have less units, attack the planets where the computer just sent ships from, and choose the size of the planet you choose to cap first carefully (bigger = more time).
IDK about the glitch for the "Hit a Shadowdemon with a Thundercracker" achievement glitch, but for me I had to hit the final boss with it. Once I did, it gave me the achievement.
For easy and medium modes you can get away with only cannons (don't upgrade) and tack shooters (blade shooter; range if needed). May have some trouble getting through a few waves around 20 but after that it can carry you to wave 50 easy.
Numbers for keypads are 1904 or 1905 and 31596 for those of you who don't want to waste time. The first one just subtract the two digit number from the year.
To beat the game, kiting with the staff is the easiest way to beat the game. Don't worry about weapon expenses, just complete a few achievements and you will have enough for the Unicorn Staff. Past that, just do a little more grinding and pick up the wukong staff. As for what to invest your skill points into, max out survival training and Iron Body in the left tree, get nimble footsteps (it helps imo) in the the middle tree, and max out the wizard tree (upgrade your tidal wave last, its damage compared to your staff makes it irrelevant). Buy Defense rings and %Defense bracelets. For your last ring buy whatever you want. If you are grinding money, damage the 3rd door until red fat guys spawn. Farm them for the moolah.
The coolest feature imo is the mini replay of what you did in the level in the level completed screen. It's so fun to watch myself take over the world XD.
The game feels really nice, but the terraforming feature needs to be tweaked to be easier to use... it almost feels like I'm playing a separate mini-puzzle where I'm trying to get a bunch of land the same level.
I came here looking for a continuation of the SFH story, but didn't quite find what I was looking for. There were many aspects introduced but I felt that some of them were unnecessary. The unlocking of the different classes really ticked me off. I have always been a big fan of the sniper class, but I'm forced to play a TON to even unlock it. And once I do, I have to keep rerolling heroes until I get one not-so-bad flaws. Then after that, I have to grind to lvl up my hero. Also, before, I could just play my fav class with my fav gun (intervention with dat 99 accuracy :D) and carry the match even if my team didn't do much, but now I have to lvl up EACH INDIVIDUAL hero, or they will feed with their default weapons and lose the game no matter how good I do, which adds way too much grinding. I also have to buy higher lvl weapons every time they level up. All in all, SFH3 has been kind of a let down for me, and I hope the next one will be much better.
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