You'll get these as you play the story.
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Welcome to the City of Robots
Complete the tutorial levels - You get this after Chapter 1.


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Not alone anymore!
Find Diana - She'll be in 2-5.


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Nothing is the same anymore
Reach chapter 7


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The world is safe!
Kill PAL 9000

You'll need to do specific things mostly with a specific character.
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You are following the wrong leader
Put a Fake Totem - Use Diana's 3rd item, you will need enough hunters saved to unlock it. I had 4 of 10 saved when I did it.

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Get back to the rescue!
Save the scientist held in floor 2-1 - You will need Karen, you unlock her after completing 5-4. Return to 2-1 to do this, be aware that there will be strong robots there. It will be near the start.


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Robot Energy Drink
Grab an Energy Drainer - You'll find an Energy Drainer in 6-1 when you go to the left side of the level from the entry elevator, if it's not there make sure to save some more weaponsmiths.



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Amazing Princess style!
Complete floor 8-4 using only the Amazing throw


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You can't touch me!
Complete floor 8-5 with Laura without getting hit


Finish the level normally first. Provided you rescued enough weaponsmiths, then I recommend grabbing the Homing Missile weapon first on the way to the north switch. After activating it, just proceed directly to the exit, you won't need to spend more than 3 or 4 activations of the weapon to reach the elevator going down, after going down the elevator just use the weapon once or twice before going back up right away, the way should then be pretty much clear to the exit. Beware the Spike conveyor belt section, it can be tough.

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Tough enough
Complete floor 9-1 with Diana without grabbing bonuses


Not much advice I can give here, don't dwell too much on enemies, and focus on going to the exit than saving scientists if you have yet to save them, will make it easier and less stressful on you.

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Harder Better Faster Stronger
Complete floor 9-2 with Karen in less than 4 minutes


Like all these other ones, complete the level normally first, afterwords you'll alright know the way, especially with Karen's map and you won't need to flip the exit elevator switch.

What have I done?
Kill 1000 enemies


You'll likely have this by the end of the story by just playing normally. If you still need more kills go to 3-2 there's a safe area to farm at the start and a slightly more risky one midway through it.





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Elite killer
Kill 100 elite enemies - They start spawning in new areas you unlock with Karen and in chapter 6 and onwards. You'll probably have this or be close to getting it by the end of the story too.

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Starting to ageing...
Reach level 30 with a character - This and getting the true ending might take you the longest, especially since you can't level just one character, you'll probably get this one passively as you work towards getting the true ending. Just keep farming.

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All's well that ends well (maybe)
Watch the "good ending" - You will need to save every single scientist and then replay 9-5, this will be difficult and take you a while, as you get the weaponsmith and level up it'll get easier though.

Hope this helped even if only a little bit.