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Name: Gravity Crusher
Attribute: DARK
Level: 4
Type: Warrior/effect
ATK: 2000
DEF: 0
Effect: This card cannot attack the turn it is normal or special summoned. If you control a face-up "Gravity" monster: You can special summon this card from your graveyard; if this card is special summoned this way, banish this card when it leaves the field.

Name: Gravity Thrasher
Attribute: DARK
Level: 4
Type: Warrior/effect
ATK: 2100
DEF: 0
Effect: This card cannot be normal summoned/ set. You can special summon this card (from your hand) by sending one Gravity monster from your hand to the graveyard; if this card is special summoned this way, banish it when it leaves the field.

Name: Gravity Circler
Attribute: DARK
Level: 4
Type: Spellcaster/tuner
ATK: 1000
DEF: 1000
Effect: This card is treated as a level 2 monster for synchro summons, except the synchro summon of a DARK Dragon-type monster. Once per turn, you can activate one of the following effects:
*Special summon one of your Banished "Gravity" monsters
*Banish one "Gravity" monster from your graveyard.

Name: Gravity Levia
Attribute: DARK
Level: 5
Type: Sea-Serpent/effect
ATK: 2000
DEF: 1600
Effect: if you control no monsters You can normal summon this card without tribute. This card Gains 100 attack for every card in your opponents hand. If this card battles an opponents monster, you can banish this card and the opponents monster at the end of the damage step. During your stanby-phase, if you control no monsters, special summon this banished card.

Name: Gravity Serpent
Attribute: DARK
Level: 3
Type: Reptile/Effect
ATK: 1200
DEF: 600
Effect: As long as this card remains face-up on the field, your opponent cannot target other "Gravity" Monsters with card effects or for attacks. When this card inflicts battle damaged to your opponent's life points, you can special summon one "Gravity Serpent" from your hand or deck. When this card leaves the field: Banish it.

Name: Gravity Hound
Attribute: DARK
Level: 2
Type: Beast/Tuner
ATK: 800
DEF: 500
Effect: The normal summon of this card cannot be negated. When this card is normal summoned: Cards and Effects cannot be activated. During the turn this card is normal summoned: your opponent cannot activate spell or trap cards until their next turn. Once per turn, you can target one non-tuner "Gravity" monster you control: increase it's level by up to two until the end phase.

Name: Galaxy-Eyes Graviton Dragon
Attribute: DARK
Level: 8
Type: Dragon/Synchro/Effect
ATK: 3000
DEF: 2500
Effect:
1 Gravity Tuner + 1 or more Gravity Monsters
When this card is synchro summoned: banish all set cards your opponent controls. When this card declares an attack, your opponent cannot activate spell, traps or monster effects until the end of the damage step. If this card destroys a monster in battle: banish it instead of sending it to the graveyard, and if you do, this card gains 500 attack.

Name: Neo Galaxy-Eyes Graviton Dragon
Attribute: LIGHT
Level: 12
Type: Dragon/Synchro/Effect
ATK: 4500
DEF: 3000
Effect:
2 Gravity Tuners + Galaxy-Eyes Graviton Dragon
This card cannot be special summoned except by synchro summon. The synchro summon of this card cannot be negated. This card cannot be targetted by Card Effects. When this card is Synchro summoned, Banish all cards on your opponents side of the field, in their hand or in their graveyard. This card gains 500 attack for every banished card. If this card would be destroyed, you can Banish one card from your hand instead.

Name: Gravity Slasher
Attribute: DARK
Level: 5
Type: Warrior/Effect
ATK: 2300
DEF: 1000
Effect: If you control a a DARK tuner monster, you can special summon this card from your hand in face-up defense position. If this card was special summoned this way, banish it when it leaves the field.

Name: Gravity Tyrant
Attribute: DARK
Level: 8
Type: Warrior/Effect
ATK: 2000
DEF: 2800
Effect: When this card is tribute summoned, you can special summon one "Gravity" monster from your deck. This card is treated as a level 6 monster for the synchro summon of DARK dragon-type monsters.

The way I see Neo-Galaxy Gravity Dragon is as far as effect go is combination of Celestial Dragon (now named Star Eater) and Photon Dragon with a little of the Six Sams effect (using hand instead of other gravity monsters) I could see Macro making this archtype a pain in the rear to deal with as well as other banish support cards.

I like the idea Oucyan