The six stats are:
This increases how quickly your character will move. The higher upgraded it is, the faster you will move from one end of the field to the other.
This increases the force when you kick the ball. The higher upgraded this is, the further the ball will travel when you kick it, and the faster it will go.
This increases your ability to jump. The higher upgraded this is, the higher and further your character will jump in the air.
This increases your character's ability to dash. The higher upgraded this is, the further your character will move when you use the dash. You can use dash by pressing left or right twice fast.
This increases how quickly your power bar refills. The higher upgraded this is, the quicker you will be able to use Power Shots.
This increases the maximum number of balls you can have at once in survival. The higher upgraded this is, the higher your maximum ball count will be.
In any single-player game mode while you are on the player select screen there is a button that says upgrade in the bottom left corner of your screen. Click on it to purchase upgrades using points. You start with all stats at the base level and can upgrade each one a maximum of ten times. The first upgrade for each stat costs 500 points and each subsequent upgrade costs twice as much as the one before it. The last upgrade costs 256 000 points.
In any single-player game mode while you are on the player select screen there is a button that says costume right next to the upgrade button. Click on it to view/purchase Costumes. Costumes can boost any of your stats except for Survival. In order to unlock costumes you must beat the Cyborg in survival while he is wearing the costume that you are trying to unlock. Then, when it is unlocked, you will be able to see the stats that it helps. Each costume, once unlocked, may be purchased. You may wear any costume that you have purchased, but only you cannot wear multiple costumes at once. While wearing a costume, it will give you the boost to the stats that it shows in the costumes menu.
There is a little grammar mistake in the upgrade shop: It will say that upgrading speed, for example, costs "50 point", which is a grammar mistake because it should say "50 points". Similar mistake appears on track showing how many points you have: It says "My Point: ---- (How many points you have)"