Considering how easy the game was, and especially given the fact that we were allowed to carve our own path, and not linear, there should have been a final boss once all four were defeated.
Just realized I couldnt post that as formatted to show the strat. The first column is (in order from bottom to top): Poison facing right, Vision, Slow, double arrow, Slow. The second column is 4x Double arrow with a DMG booster on the bottom. Third column: Slow, Vision, Slow, Digestion facing left x2. This is what you want by lvl 10 or so anyway. As far as building order is concerned, I would do the poison, vision slow first, followed by the double arrow stack middle. Then build toward the goal. Once this is done, you can start replaceing double arrows with digestion blocks, since bosses are your only real concern when you accumulate souls and your sword kills the minions.
If anyone is having trouble @ Survival just go:
Double Arrow Double Arrow Slow
Double Arrow Double Arrow Double Arrow
Slow Double Arrow Vision
Vision Double Arrow Double Arrow
Poison Double Arrow Slow
This will last you a long time, and as the bosses pile up and cheese your stuff, dont rebuild the things in your left and right stacks as much, unless they cheese your vision, which you need. Instead rebuild the middle as digestion blocks facing left. As you accumulate souls your sword should take out the minions without much easy (if you have upgraded your sword with both upgrades). You can probably do fine without a right most column.
MAKE SURE THESE 3 COLUMNS ARE ONLY APART BY ONE BLOCK.
This was my strategy and no unit ever even touched a stuffed animal.
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