I really like this game. Would love more. And I like the system of having limited character options, so that you have to adapt your playing strategy to what you're given. I would actually enjoy more restrictions in that regards, unlike many of the commenters!
JadeDragoon - complete missions to increase your score multiplier, then focus on combos, and upgrade flame scrolls. I got the Hard achievement with score multiplier max x35 and flame scroll lvl 3.
[cont.]
5. Streetlights/bamboos count as combos. They are often placed so that if you take the wrong path, you can still maintain your combo. Use them.
6. Coins become much easier to collect when you've played a bit. Focus on keeping the combos going, and you'll have constant dings of money awards for the combo length. As a secondary objective, following the lines of money and collecting gold scrolls gives you a reasonable bash as well. I now aim to get over 500 gold per run. Don't spend coins on shadow cloaks/multipliers/cats. You'll get a fair amount of the first two through free cat spins, and will need to use them for missions, so save them up.
Tips on how to play:
1. In the beginning, focus on missions. This raises dramatically how high you will score, and there's no point focusing on anything else until you are better at the game.
2. Follow the zombies - they are placed as they are for a reason. So if there's a zombie left in the line as a beserker is coming, it's because you are able to hit that final zombie (and keep the combo going). As the game speeds up, it becomes less necessary to hit these.
3. Pressing down immediately ends a jump. This is incredibly useful if you mistakenly jump (e.g. during a fatso launch). Also get into the habit of pressing down as you reach a ledge, to ensure you hit the first zombie (and maintain your combo).
4. Look ahead. You need to know what is coming up.
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I like the upgrade system. As the game currently stands, the upgrades aren't necessary; theoretically, you could get that hard badge on your first run. Of course you won't, but that's nice because you can see that YOUR skill has improved, not your character's. Upgrades are just a nice bonus to boost you up a little higher than you objectively are (flame scroll for score, for example). If upgrades did more, or there were more available, then they would either be overpowered or a requirement. I don't expect to max upgrades - that's okay as well. I would rather have an option to upgrade it further that I don't use, than have too many coins and nothing to spend it on.
This is a very, very good game. I haven't found much at the moment that holds my attention, but this does. Having to move the canons around on the same tower, nice feature.
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:)