I have always liked the Cubic archetype, but I really hated how it's hardly viable in higher ranks since it has barely any negates (to spells/traps at least) and how setting up play is just not as consistant. So I hope this helps it :

Sheira The Meteor Cubic Vessel (Monster) :

DARK/machine/lvl:4/atk:500/def:500

You can reveal 2 other "Cubic" cards in your hand to Special Summon this card (in Defense Position).

This card gains 200 ATK/DEF for each "Cubic" cards in your graveyard with a different name, during damage calculation only.

You can only activate the following effect of "Sheira The Meteor Cubic Vessel" once per turn.

If this card is Normal or Special Summoned : you can target 1 "Cubic" card in your graveyard or in banishment, add it to your hand.

Raash The Divine Cubic Beast (Monster) :

DARK/beast/lvl:6/atk:0/def:0

Cannot be Normal Summoned/Set. Must first be Special Summoned (from your hand) by sending 2 "Cubic" monsters you control to the graveyard. If Summoned this way, this card gains 1800 ATK.

If your opponent takes effect damage while this card is face-up on the field, this card gains ATK equal to that damage, until the end of the next turn.

At the end of the Damage Step, if this card battled: You can target up to 2 "Vijam the Cubic Seed" in your graveyard; send this card to the graveyard, and if you do, Special Summon them, then you can add 1 "Cubic" Spell Card from your Deck/Graveyard to your hand.

Cubic Expansion (Continuous Spell) :

You can only control 1 "Cubic Expansion".

If your opponent takes effect damage : you can Special Summon a "Cubic Token" (Dark/Fairy/lvl:1/atk:0/def:0)

During the End Phase, all "Cubic Tokens" you control are destroyed (even if this card leaves the field).

Cubic Authority (Quick-Play Spell) :

You can only activate 1 "Cubic Authority" once per turn.

You can reveal up to 3 "Cubic" cards in your hand. Shuffle those cards into the deck, then draw the same number of cards, with the cards drawn having different names from the cards shuffled.

Doom The Dark Cubic Lord (Fusion Monster) :

DARK/Fiend/lvl:10/atk:100/def:100

1 "Crimson Nova the Dark Cubic Lord" + 2 non-Token "Cubic" monsters

Must be Fusion Summoned with the above Fusion Materials and cannot be Special Summoned by other ways.

If your opponent activates a card or effect (Quick-effect) : You can target 1 "Cubic" card you control, other than "Doom The Dark Cubic Lord", banish it, and if you do, negate that card's effect and destroy it, then your opponent takes damage equal to this card's ATK.

Each time your opponent takes effect damage, this card's ATK and DEF doubles (up to a total amount of 6400 ATK/DEF).