I am now well beyond day 200 in a game.
The game becomes extremely slow.
And the monsters no longer aim for the castle but either, do not move at all, or, wander around in random directions, including running away from the castle.
A screenshot from that game:
Yeah, I ended up with basically same strat, except my tower line was slightly more removed, with a few in the path leading to it, because the enemies hug the edge of the tile, so the opposite line can't really hit them. Surprised they are able to handle it when your first towers get corrupted. I guess the path is just long enough. That's some good starting RNG!
