Perfect Style 30
Reach 100% style in a single fight by using a varied combination of attacks.
This can be combined with the "Artful Dodger" achievement. I got this on Chapter 2 by accident. I was going for the Artful Dodger achievement and ended up dying and still got the achievement. In short, do all the dodges, get some combos, punch, kick, and power punch some enemies.
Fight Marathon 30
Defeat 100 or more enemies during a single fight.
If you play the game normally you won't get this by accident as there aren't any fights with 100 enemies. Even beating 20 levels of Survival: Horde will only net you around 85. The best place to get this is Chapter 7. As long as you don't destroy the totem the enemies will continue to respawn 3 at a time. Just keep killing them and the achievement will pop once you reach 100. An alternate location would be Chapter 2. As long as you don't close all the cargo containers enemies will continuously respawn. However, the enemies respawn a lot faster in Chapter 7.
Shoot a Giant in the head with the Magic Bow.
This can be done in Chapter 12. Once you destroy the barriers and defeat the few enemies that charge at you, the giant will come out next round. Just aim up and shoot him in the face.
Kung-Fu Party! 20
Complete a multiplayer fight against 3 or more players controlling enemies.
This can easily be done by yourself with 3 controllers. Just go to “Custom Game” and select multiplayer and make sure to have the rounds set to one. Press A on the controllers and select your baddies. Start the fight, beat the 3 enemies and once the fight is over the achievement is yours.
Artful Dodger 15
In a single fight, perform a dodge, duck, flip dodge, backflip dodge and jump dodge.
You can get this as early as Chapter 2. It’s very simple just perform all of the dodge moves. You’ll know when you’ve performed the move as it will tell you on the screen.
Dodge – Move to the side
Duck – Simply duck down
Flip Dodge – While facing the enemy, jump slightly forward and throw your arms up and forward (as if you were diving into a pool)
Backflip Dodge – While facing the enemy, jump slightly backward and throw your arms up and back
Jump Dodge – Just jump a low attack.
The in-game tutorials will show you how to do these dodges.
William Tell 15
Score five consecutive hits using the Magic Bow.
The earliest you can get this is Chapter 6. As long as you hit any enemy 5 times in a row without missing you'll get this achievement. I waited until I knocked the mini boss out of the tree and when he was charging I shot him. He will stagger giving you another opportunity to hit him again. Repeat 3 more times and the achievement is yours.
In Chapter 4: Helmet Blunder, defeat the Shadow Guard without using Ground Shaker.
Once you get to the checkpoint, an in-game tutorial will teach you how to do the Ground Shaker. You have to do the Ground Shaker to continue and then you’ll instantly have to fight the Shadow Guard. What I did was wait for him to do his slow swinging attacks and once he got pretty close I’d jump over him power punch him a few times and back away. I continued this until he was defeated. Also watch out for his Ground Shaker attack. Just jump straight up to avoid.
He pretty much has two health bars. Once the first one gets down about halfway a few other enemies will show up. They can easily be taken out. Once the first bar is depleted, his helmet falls off and the second health bar takes no time to eliminate.
Pick on Someone Your Own Size 15
Finish off a Giant while giant-sized yourself.
Chapter 10 is where you'll get this achievement. Once the giant spawns look for a shrine to break to get the green orb. This will turn you into a giant. If the power runs out, just wait for another one and finish him off. Another way is to get his power down before you get the green orb.
Win a single fight without physically touching any enemies yourself.
What I did was set up a custom game with only one round and one enemy. Use only lightning to defeat them. Simple as that.