The control scheme is rather confusing to me, as I like using space to jump. Space being the main function that can't be changed just makes it hard for me.
Seems to do a equipment and skill set up similar to MapleStory.
Tips for new players: Choose one weapon profession and stick with it.
From what I see you have swords, bows, or magic.
Swords: Invest points in Strength
Bows: Invest points Agility
Magic: Invest points in Intellect.
Invest points in stamina as needed for equips.
All the game boils down to is upgrading your units enough so they can immediately rush the castle after spawning. Then if you can't win like that, you grind previous levels for more gold to upgrade your units.