From Melty Blood Actress Again Wiki

Melty Blood Actress Again introduces moon styles, which are kind of like grooves in Capcom vs. SNK 2. After selecting a character, you can select between Crescent, Half Moon, or Full Moon as a style.

Crescent Moon

In general, plays like how Melty Blood Act Cadenza did. A good mixture of speed, power, and comboability. Has the most control over meter out of the three styles.

• Can reverse beat

• Meter goes up to 300%, can go into HEAT mode by pressing 5E/5A+B+C anytime meter is over 100%. During HEAT mode, red life slowly regenerates. Can go into BLOOD HEAT mode by pressing 5E/5A+B+C on the ground anytime meter is in MAX mode. During BLOOD HEAT mode, all red life instantly converts to yellow life. Heat activation has invincible startup, is unblockable, and wallslams, but has recovery.

• Can dodge both in the ground and air by pressing 2E/2A+B. Doing an air dodge makes your character face the right direction, and weakens the guard meter

• Can circuit spark both in air and ground by pressing 5E/5A+B+C when getting hit in MAX meter mode

• Has EX Shield and Normal Shield.

• Shield bunker performed by pressing 214D, works kind of like a guard cancel or alpha counter. Costs 50% meter, does a bit of damage

• EX guard performed by guarding an attack right before it hits, like a Garou Just Defend or a Guilty Gear Instant Block. Restores guard meter when successful

Half Moon

Good comboability, and power is generally low but damage can be very high with good execution. Has the least control over meter out of the three styles. Suited to a rushdown style of play.

• Can reverse chain

• Meter goes up to 200%. Cannot manually activate heat, but once meter reaches 200%, your character will automatically go into HEAT mode. During HEAT mode red life slowly regenerates. If your character gets hit while in HEAT mode, you will automatically circuit spark. EXCEPTION: If your character is getting comboed by the opponent and you reach 200% during the combo, then you can choose when to spark during this time.

• Can dodge both in the ground and air by pressing 2E/2A+B

• Cannot EX shield, can only normal shield. If shield is successful, your character will perform an auto shield counter, which launches the opponent and allows a followup combo.

• Shield bunker performed by pressing 214D. Costs 100% meter, but is faster and has better recovery than the shield bunkers of the other moon styles. Also does 0 damage

• Cannot EX guard

• Gains a 6AA followup to 5A

Full Moon

Emphasis on power, more damage per hit, but less comboability. If you like Guilty Gear, play this style!

• Cannot reverse chain. Has basic weak->medium->strong chain sequence. There are also special rules within the button strengths. A’s have no restrictions, B’s are normal->crouching normal->command normal(ex: F-Ciel 5B2B4B), C’s are normal->command normal and crouching normal->command normal.

• Meter goes up to 300%. Cannot manually activate heat if meter is below 300%. At 300%, your character goes into MAX heat mode. At MAX, your character can go into BLOOD HEAT mode by pressing 5E/5A+B+C.

• Also, in MAX heat mode, most normals and specials can be cancelled by doing an INITIATIVE HEAT, which is 5E/5A+B+C while the normal or special is being performed. Kind of like a GG Roman Cancel, but Initiative Heat cancels the attack and also puts your character into HEAT mode. Initiative Heat instantly converts all red life into yellow life. Normals can only be IHed on hit or block, specials can be IHed on hit, block, and whiff.

• Can circuit spark both in ground and air by pressing 5E/5A+B+C

• If not in MAX or BLOOD HEAT mode, pressing and holding 5E/5A+B+C on the ground will make your character enter a charging animation. Meter will rise at an accelerating rate until 5E/5A+B+C is released.

• Cannot dodge or air dodge

• Cannot EX shield, but can normal shield. Upon successful shield, your character can either cancel into a special or do a SHIELD COUNTER by inputting 236D. 236D launches the opponent and allows a followup combo.

• Shield bunker performed by pressing 214D. Costs 50% meter

• Can EX guard

Referenced from: http://www.meltybread.com/meltywiki/melty-blood-actress-again/mbaa-moon-style-differences/