Oh, and with the nightmare guy...you have to double jump over him, and then time it so that the meteorites go over it. Once that happens, the nightmare guy should be injured, releasing dark crystals. Collect them to cause damage to it. You'll learn its pattern in a night or two. Also, try to find the Squarian city. Buy double jump first, and avoid dash unless you are going for 100% completion (which can be done after the first game completion). Regen is also needed. Radar is useful if you can't find gems, but otherwise is a waste. Buy health from the guy for 50 a pop. All together, with max skills (talking to everybody: pumps & doors, squarians, and roundians gets you knowledge to improve how fast exp is gained), the nightmare should be easy to beat.
Reproduction & Strength are the most important. If the enemy is coming at you, move yourself out of the cell (unless you are below 3) and then move back into it. Agility is the next important, but the other two are not needed at all. In the beginning of the game, rush to get as many empty cells. Ignore losses at first, but make sure on cell has at least 45 in it. After that, it becomes a defense game. When there are multiple enemies attacking the same cell, do not defend it. Move your guys out, and wait for one win it. You'll take less casualties, and it will be disastrous for both.
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