How do you beat the 13th level? I've tried everything. You can get a 19 and still have perfect. I think it's impossible!! I've tried several times. Mages, rouges, ninjas, archers seem to work for the first 3 levels and then mages average until level 11 where Melee + mages rock> IDK!!! I'd like to see what the secret level is.
You must be missing something very obvious because this is one of the easiest battles in this quite easy game.
I'm guessing that you simply don't have all the available upgrades yet, which is why you have so much trouble. Redo all the battles from the start to get 5/5 gems as those gems are then used for upgrades, then tackle the last fight again.
The most important unit in this game is the Fire Archer. Fire Archers kill, Guards and Mages slow down the enemy, the rest is fodder. Forget about the Elves, they suck. To really get a good bang for your bucks you need to get at least one upgrade above Elves so you get poison. So stick with Fire Archers at first.
Another very important unit is the Mortar. Thing is, you will never ever need more than a single one of them. The only reason why Mortar is so useful is because of Skeletons which take age to kill with Archers, even with the Fire Archer fire boost. Mortar will tear thru the Skeletons like a hot knife in butter and can be useful with the most numerous and tightly packed weak enemies too so it is not a complete waste. On maps on which there is no Skeletons at all then you would be better off with no Mortar at all and more Fire Archers.
A very important aspect of this game is to gather enough soldiers at a single point to be able to make a stand if the enemy is strong or numerous enough to get past your archers. In the #13 fight, use the 3 half-circle closest houses from the ship which will allow you to get all 3 squads at the same spot (if you look closely you'll see that all the circles overlap, right in the middle of the road leading to your defense). Purchase 3 soldiers from the left and right houses and 2 soldiers + 1 mage from the top house (said mage will in time be upgraded to a Druid). The house right above should house 3 mages which you can gather at the exact same spot. Then use the other two houses above to train 3 Archers each. You're set. Train your Archers to Fire Archers one at a time and upgrade one of the Fire Archers to Mortar at the right time to stop worrying about Skeletons.
Before you get the Mortar, use the nifty mortar shots from the ship to destroy the Skeletons. It doesn't matter if the Skeletons don't die in one shot, the whole point is the fire damage which will get rid of them by itself.
One very interesting aspect of this game is a nice conundrum with most unit upgrades: most high end upgrades are actually worst than the previous model. For example, you will never want to get stuck with Elves rather than Fire Archer because Fire Archers are already decent enough PLUS have access to fire which double their usefulness. Many units will plummet to their death with time when set on fire, and the Fire Archer still continue to fire at the same time. The Elves just have higher to hit ratings and damage and that's it... Not worth the money. The next upgrade, after the Elves, is however better than the Fire Archers and is worth it. I'd still recommend keeping at least one Fire Archer in a group though so you can enjoy damage stacking. Or maybe the opposite: train only one top Elf in an Archer group to get benefit from poison.
The same thing can be said about the healer. A healer, plainly said, suck. You just upgraded the most useful mage (the second upgrade of the type which slow down the enemy) and then you use a little more money to turn that powerhouse into a unit which do nothing but heal your troops very slowly... SO not worth the upgrade. A Priest now, that unit rock. Because it also boost the grunts at the same time and turn the lowest of unit into a powerhouse too. The Druid is simply even better.
All this to say that while considering those units (Elves, Healers, Ninjas, HammerDwarves, Electric Mage, etc), you are actually better off waiting until you can afford to upgrade directly to the next tier. For example, the electric Mage is so underpowered versus the third level freezer... But then, as soon as you get chain lightning this unit kick ***. And this, my friend, is the conundrum.
