A broad overview of the gameflow can be found here. The sections below are a bit more specific about the mechanics.
How does Health work in Vanguard Princess?
Very simply, there are two tiers of Health in VP. The High tier has 1000 HP, the Low tier has 900 HP:
High: Yui, Haruka, Lilith, Luna, Natalia
Low: Kurumi, Saki, Kaede, Eri, Ayane
This is the largest part of life differences between characters, but there are some subtle other aspects. The unfortunately complicated, but real answer, is that the damage a character takes is based on properties of their hittable-boxes and other strange things.
Characters take extra damage while crouching, jumping, or from being counter hit.
The amount of damage you take in these states is increased a bit. Again, it's based on hittable-boxes, but as a rule of thumb you can think of these numbers:
Crouching: ~17% Extra Damage
Jumping: ~27% Extra Damage
Counter Hit during a Reflect: 0% Extra Damage
Counter Hit during Everything Else: 0% to 80% Extra Damage, Depending on the move
These damage increases only ever apply to the first hit that connects, not additional hits of the combo.
Damage taken can be inconsistent between characters and situations.
Since damage is based on the character getting hit's hittable-boxes and other esoteric things, you get some odd situations where damage is different than what you'd expect. Some characters however, seem to take less damage than others on an overall basis. An overall rule of thumb you can follow is:
Takes Highest Damage: Kaede
Takes High Damage: Ayane, Eri, Kurumi, Saki
Takes Low Damage: Luna, Yui, Haruka
Takes Lowest Damage: Lilith, Natalia
As a result (coupled with the Life Tiers), Natalia can end up having the most life in the game by a small margin, and Kaede the lowest by a small margin. The differences are fairly subtle of course, and don't apply to all situations.
Characters can tech in the air after being hit. The time until you can tech varies with the attack you are hit with. After teching, your character cannot be hit or thrown until she touches the ground. Currently, the only known exception to this rule is Kaede's j.236X. A and B causes your character to back tech. C and D cause your character to neutral tech. You can use your assist right after teching.
In general, characters can be thrown while standing, crouching, walking (backwards or forwards), and running forward. They can also be thrown while in the middle of certain attacks and during a Reflect. Characters cannot be thrown while in blockstun or hitstun, while in the air, and when back or forward dashing (not running). Only Kaede and Lilith can throw aerial opponents.
Throws always do the same damage
In fact, damage scaling seems to be entirely ignored for throws. Kaede's air throw always does 100 damage, regardless of when it is used in combos.
Reflect is used by hitting E and is much like a parry in other fighting games. You have to be standing or jumping to reflect high attacks and crouching to reflect low attacks. Mid attacks can be reflected in any way. Air unblockable attacks can be reflected while jumping. Successfully reflecting an attack will increase your meter by ~28%, plus another ~10% for using an attack after the reflect. Throws, projectiles, and assist attacks cannot be reflected. Certain moves may only hit once but have to be reflected multiple times. Good example of this is that you have to reflect Eri's 22A/B twice, even though the move only hits once. Same goes for Saki's 623B. It might be that, reflect only effects the current hitbox of a move. If that hitbox changes, even if it doesn't count as another hit, you will have to Reflect it again.
All assists have four different attacks and a proxy guard. A rule of thumb for the amount of support meter each attack uses (from low to high):
4D -> 5D -> 6D -> 2D -> 3D
with 4D often costing less than 1 Level, 5D costing around 1 Level, and the others costing 2 or 3 Levels.
This meter fills own its own at a pace specific to the character you use. Blocking attacks will decrease the meter in proportion to the strength of the attack. The rate at which blocking decreases the meter is also affected by your main character.
All assists attack in the direction your main character is facing, although some assist attacks will change direction if a crossup occurs (notably Sierra's 6D). All assist attacks can be blocked, it does not matter if it is while standing, crouching, or in the air. Blocking direction is relative to your opponent's position and NOT the assist's. For example, Eko's 6D causes her to kick behind your opponent, but your opponent still only needs to move away from you to block it. The same goes for when your opponent crosses you up, keep pressing away from your opponent to block.
The assists move slower than your main character, and they can only move to and attack from certain points on the ground. Keep this in mind because if you run towards your opponent, your assist will not be there to help you immediately.
Used by hitting 4D or 1D. (Does not work with 7D so you must use 4D or 1D if in the air.) This neutralizes all projectiles and assist attacks from the opponent for as long as the assist is active. For example, using the proxy guard against a Juliet 3D keeps the proxy guard active for a while, during which any new projectiles your opponent sends out will also be neutralized.
If you get hit while using an assist, you will be barred from using your assist for a limited time and your support meter will drop to just below Level 1. Also, whatever assist attack you used will no longer inflict damage, with one exception for each assist. Approximate in-game time to recover from Support Counter is as follows:
4D and 5D: 3 seconds
2D and 3D: 6 seconds
6D: 5 seconds
If two characters' Reflect overlap, they will essentially parry each other. Both players will get meter for it.
On rare occasions: Your character may get stuck in mid-air. It is sometimes possible to mash out of it. Getting hit will return the character to normal. Occurs most often with Lilith.
On extremely rare occasions: When moving away from the corner, the corner may move as well, thus shortening the stage.
Saki's Liberty Art sometimes doesn't damage scale when performed in a combo.
- Some characters' feet during a jump take less damage than the rest of their body.
- Characters have different "jumping speeds". Just compare Kaede to Haruka.
- Using Reflect early in a jump will give you more air time.
- Teching gives your character more air time.