The DLSite .zip file includes a "config-all.dat" file. If you rename it to "config.dat" (and delete the original), you'll unlock all CGs in the game.
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Some notes:
* The downward direction is a blindspot. I suggest "Down-attack" while falling, so that you at least have a hitbox that can somewhat protect you. You need to use this attack to bounce off of some enemies and reach some coins multiple times throughout the game.
* While on the ground, down-jump allows you to dodge backwards with a slight amount of invulnerability frames. This was useful only in two points in the game, both on the final level. 1. When the "jumping zombie" (who jumps only when you do) is blocking the awy, you can down-jump past him much more easily. 2. The final boss's quick attack patterns are so fast, that your invincibility frames are actually useful. Down-jump may be useful for speed-running this game, since its very fast. Most enemies are too slow however, so the invincibility frames don't seem very useful outside of the final boss.
* Up-attack is a sumersault / flash kick style attack. This was very useful against the stupid butterflies in the 3rd level. It attacks all around you, even behind you.
* Double-Forward-attack is a thrust that does extra damage and has extra range. If you can't reach the opponent, try the thrust (useful in the 1st level where some enemies are further back on staircases).
* Down-attack (crouching attacks) seem to have slightly more range.
* Double-down + attack is a sliding motion, which was useful vs grounded enemies and the axe folk for me.
* Jumping attacks have their cooldown canceled by the landing animation. A falling jumping attack into a combo seems to be the highest DPS in the game. Useful vs bosses.
