Barbarian War is the third level in Castle Crashers. For new players, it's quite hard to handle. However, once you know how things work, it's easy. The main enemies are Barbarians and the boss of this level is the Ram-Mobile.
Guide[edit]
A walkthrough for the level
Note: This guide is on Insane Mode. If you're still playing in Normal Mode, keep reading! It's better to know a little bit more :)
Let's begin!
First Wave: 5 Barbarians 
Leaving the castle, you'll find two Grey Knights 
fighting some Barbarians. Help your allies by trying to group your enemies then use your splash attack to damage them at the same time. If you know how to "air-juggling" your enemies, try that - It's an effective attacking method on Insane Mode. Some other combos work well too. Visit the Combos page and Enemies for more details.
Second Wave: 6 Barbarians
Moving to the right, you'll see a Barbarian punching a Grey Knight. Knock that Barbarian off the Grey Knight and he will fight with you. Then, more Barbarians will come, trying to overwhelm you. But don't worry, keep spamming magic and air-juggling and you'll be fine. Remember to collect food from fallen enemies in order to heal yourself.
Third Wave: 6 Barbarians
This wave is pretty similar to the Second Wave. However, this fight takes place near a destroyed catapult. You can use the broken parts of the catapult as obstacles to block the arrows from the Barbarians.
Fourth Wave: 6 Barbarians , 2 Thieves 
Keep moving to the right, you'll see 2 Thieves raiding some dead bodies. Take out the closet Thief and leave the other one. Now, a group of Barbarians will ambush you. Remember, keep spamming magic and air-juggling and you'll be OK. If the other Thief join in the fight, this could be a problem as he shoots his arrows in a straight line. However, if you know when he's about to shoot, raise your shield to block it. Note: The Thief will drop the bow when defeated if you don't yet have the bow which can be picked up.
Fifth Wave: 5 Barbarians
Moving forward, you'll see a big puddle of water. However, water slows you down, so don't walk there no matter what. Later, a Barbarian will run to you while carrying a flag. Wait until he leaves the puddle of water and drops the flag then attack him. (While carrying the flag, that Barbarian is immune to damage and water slowdown). Other Barbarians will show up and aid him. Defeat them should be easy.
Sixth Wave: Ram-Mobile
If you're low on health, cut the grass to find food to heal yourself before fighting the boss. First, the Ram-Mobile will come to you at a great speed (It'll try to ram you, so dodge) and shoot cannonballs at you (The red X on the ground indicates where each cannonball will land, so avoid it). It'll repeat this process twice before slowing down and unloading Barbarians to fight you. Just ignore the Barbarians and only attack them when you have to. If you get near the Ram-Mobile while it's moving slowly, it'll stop and fire cannonballs at you. Use this as your advantage by jumping up then quickly use the air-juggling combo to attack it as the cannonballs can't hit you while you're airborne (But it can if you stay quite close to the ground). When it's about to ram again, it'll shake itself, so get out there immediately then dodge its ramming and cannonballs attacks (see above). Repeat this until you defeat it. By the way, its cannonballs can damage the Barbarians. Note: See the video for more details about the fight against the boss.
Seventh Wave & Eighth Wave & Ninth Wave: 4 Barbarians each wave
Upon entering the enemy's camp, 4 Barbarians will come and try to kill you. Defeat this wave and another similar wave will come. Keep spamming magic and air-juggling combo to beat the waves.
Tenth Wave: 2 Barbarians
The easiest wave in the entire level. After beating this wave, you'll see a big wooden door which is destructable. Continue to the right.
Last Wave: 3 Barbarians
You'll have to fight Barbarians on a wooden bridge. After beating this wave, continue to the right and you'll see another big red door with an angry face on it. Go through the door to end the level.
Important note: After completing this level, the game will automatically save this level but this save is temporary. In other words, for example, if you complete this level - Barbarian War but not the level Barbarian Boss, exit the game (not exit to map) will cause you to lose data and you'll have to play this level - Barbarian War one more time, which also means you'll have to complete Barbarian Boss to have your data saved permanently.