Reaching rank 50 may be a serious time investment. It will take the average player a couple months of play; however, using these tactics and some buffs from Happy Cards, I was able to go from level 1 to level 50 in less than 3 weeks by playing daily with a team and focusing strictly on XP gains (starting in the final week of a traditional Special Challenge event). In addition to earning this achievement, rank 50 allows you 35 weight on the cleric and warrior, and 30 on the mage; as well as boosts your 'luck' rank eight levels which increases the odds of getting better gear as rewards. The maximum level is 60, and increases the weight cap on each character by 5 (maximum).Special note: 'Experience Up' helmet buffs only effect in-game levels (1-5) and will NOT increase the amount of experience you earn towards your rank!Special Events
: Quick XP
The quickest way to rank up is the traditional Special Challenge (not Castle Defense) or Save the King when they are available. Killing 'Slayers' or the king will net you around 100-150 XP per kill, and the matches only last 10 minutes instead of 15. To kill Slayers, try using 'Smash Power Up' and 'Uppercut Power Up' in conjunction with shield-bashing, smashing or rushing, or use cannons and ballistas to shoot them. To kill a player who is King, use warrior's rush or Berserker spin-blade and don't worry about staying alive afterwards, just die and kill him again for another 100 XP. For additional XP, kill the Bonus/Boss Monster, and/or be in the enemy castle at the end of the game.Co-op Grinding
: Unreliable XP
Since the Special event game types are not always available, you can alternatively have a large group of eight play co-op mode. The strategy here is to move the entire team up the map as fast as possible and then instead of taking down the enemy's castle gate, move the team all to one side of the castle and kill the bots that will immediately all start coming to you. By not killing the castle door, you disable any randoms or bots from tapping down the enemy's tower and ending the game earlier. This is also a great way to farm for item boxes. The problem with this approach is that if you have humans on your team who are not with the program, they'll probably have no problem breaking into the castle and capturing the Big Tower if you're killing all the enemies -- unfortunately, this is very common.
Alternatively, you may be able to get away with doing team skills in the castle endlessly with a party of 8. If you're lucky, the rest of the team won't end the game quickly and you'll be able to earn a few thousand XP every 10-15 minutes. Make sure to have as many Skill+ buffs on your weapons before doing this method to insure you always get 3 team skills by level 5. Important note about Co-op!
Co-op mode requires four players and ends when there is less than four. It will also continue endlessly without searching for new players if you don't leave the lobby. If you are trying to get in a co-op lobby with only friends, you simply must stay longer than the randoms you originally get matched with.Quick Match
: Main Event
When in Quick Match, or just as a general approach in all game types, focus on getting in team skills, capturing spawn towers, buffing teammates with clerics and mages, and killing other players as a Warrior. Being in the enemy castle when your team wins will earn you an additional 200 XP. Being the person to deliver the killing blow to the enemy gate will earn you 100 XP. Killing players who have "approached your castle" will net you additional experience (up to +100 XP), as well as killing players who are on kill streaks or who have recently killed yourself or your teammate.
The best class for XP is the Cleric. Spam skills on other players like Dash (it has a short cooldown), Heal, and Dispel. Resurrect and Sacred Armor are very good for helping a fallen teammate or buffing the fighters protecting you, but they take a long time to cooldown and should be used more strategically. By playing a more passive role as the cleric you'll be able to observe how other people play and pick up some moves from watching them fight.Fastest Possible Solo MethodEdit, April 3 2014: This game is constantly changing. The special challenges have been tweaked, new ones introduced, and most importantly the Slayers are now far less vulnerable to being smashed, making killing them a bit trickier than it used to be.
Using this approach, I was able to reach level 60 in under a month after resetting my save, however I am invested in Happy Wars for more than your average XBLA game so this solution may not work for many. They have a Happy Card sale roughly every two months. Happy Cards can provide low-level players with some decent buffs at the expense of some actual money, but they give random rewards. It is possible to receive these buffs from simply playing the game, however it is extremely rare.
If you want to keep your Happy Cards purchase in the realm of the cost of an average XBLA game, your best bet is to earn 5-6 Warrior stickers from the game's Mission Mode and then use them on weapon packs and cross your fingers that you get something with Smash Power-Up Lv3 on it and maybe a Rush+ so you can kill the enemies in Special Challenge with ease. Then just put Smash Power-Up Lv3, Lv2 and Rush+ on a weapon and that warrior is ready to send Slayers flying off cliffs for easy XP. Unfortunately if you are in the realm of $10-20 the Happy Cards are a huge gamble.
For further reading, I posted a guide for 60 quests as well as a general Happy Wars strategy guide here: