Finally released to the public, after much hard work. I will of course be updating these over time.

Monsters

Damage Mediator (FIRE)
**
[Spellcaster/Effect]<----(Should I change this to Beast-Warrior?)
During the End Phase of a turn you took Battle Damage, you can draw a card; Discard this card from your hand and both players increase their Life Points by the damage you took. When this card is discarded by a card effect, (including its own): Select 1 Continuous Trap in your deck and set it on your side of the field. That card cannot be destroyed while set and cannot be activated on your opponent's turn.
200/300

Wiseman Alius (DARK)<----(OCG: Another Wiseman)
****
[Fiend/Effect]
While you control a face-up "Elemental Hero Neos", you can Special Summon this card (from your Graveyard). While you control no monsters: Discard this card; Special Summon 1 "Elemental HERO Neos Alius" from your deck if face-up attack or defense position, then your opponent selects 1 level 4 monster from their deck and special summons it in the same Battle Position. During the turn this effect is activated, cards cannot be set or flipped face-down. This face-up card's name becomes "Yubel".
500/0

Dark Honest (DARK)
****
[Fiend/Effect]<----(Compatible with Darkness Neosphere)
Discard this card from your hand and return one DARK monster you control to your hand; You can conduct an extra Normal Summon this turn, yet that monster must be DARK. During either player's Damage Step, when a face-up DARK monster you control battles: You can banish this card from your Graveyard; that monster gain ATK equal to the ATK of the opponent's monster it is battling, until the End Phase.
1100/1900

Katana Slasher (DARK)<----(Effect version of Saber Slasher)
*****
[Machine/Effect]
This card cannot be Normal Summoned or Set, except by tributing 1 Level 1 monster you own. Negate the activation of cards and effects that target this card. Each time a card's activation or effect is negated by this card's effect: This card gains 100 ATK. While this monster's DEF is lower than its original DEF, this card gains ATK equal to the difference. During the End Phase of a turn that this card leaves the field: Target exactly 3 level 1 or Rank 1 monsters in your Graveyard; Special Summon those targets, but only if all three are still in the Graveyard.
1450/1500

Dark Sephylon (DARK)<----(This is how DARK decks were intended to be)
**********
[Fiend/Effect]
Cannot be Normal Summoned or Set. Must be Special Summoned (from your graveyard) by having 10 or more DARK monsters in your Graveyard, and cannot be Special Summoned by other ways. Once per turn: You can Special Summon 1 Level 8 or higher DARK monster from your hand or Graveyard, but its effects are negated and its ATK becomes 4000.
4000/4000

Yubel - Lightray Reincarnate (LIGHT)
***********
[Fairy/Effect]
This card cannot be normal summoned or set. This card cannot be Special Summoned except from the hand or Graveyard by banishing 1 card in your graveyard while you control "Yubel - Terror Incarnate". While this card is in the deck: Its attribute is DARK. While this card is in the Graveyard or on the field: cards and effects cannot be activated in response to the summon of "Yubel" or "Lightray" monsters. This card cannot be destroyed by card effects, and you take no effect damage while you control this face-up card. If this card would be banished: select 1 card in either player's graveyard; banish that card instead.
0/0

Yubel - The Galactic Horror (DARK)
***********
[Dragon/Xyz/Gemini]<----(Summon this in a turn that you haven't yet normal summoned)
2 level 11 "Yubel" monsters
This card is treated as a Normal Monster (and not an Xyz monster) while face-up on the field or in the Graveyard. While this card is face-up on the field, you can Normal Summon it to have it be treated as an Effect Monster with this effect:
● This monster's effect(s) cannot be negated. Once per turn: Detach 1 Xyz material; Special Summon 1 Fiend-type monster in your Graveyard with 1500 or less ATK and inflict damage to both players equal to 100 x the summoned monster's level. If this card would be removed from the field: Add cards from your graveyard to your hand equal to exactly the number of other cards on the field; destroy all other cards on the field instead.
3000/3000

CXyz Yubel - The Sweet Dream (DARK)
************<----(Rank 12, my pride and joy. Use in a Yubel deck, or with Dragons! FGD + 2 DARKS + Galaxy Queen's Light)
[Dragon/Xyz/Effect]
3 or more Level 12 DARK monsters
While this monster has xyz material attached to it, its effects cannot be negated, and this card cannot be flipped face-down. You can detach 1 Xyz material from any monster you control: Inflict damage to your opponent equal to 200x the total combined level of all banished Dragon-type monsters. If this card has "Yubel - The Galactic Horror" as an Xyz Material, it gains these effects.
● This card gains 1000 ATK for each "Yubel" and "Wiseman" monster attached as Xyz Material to this card.
● Once per turn, you can detach 1 Xyz Material from any monster you control and select up to 3 "Yubel" or "Wiseman" Monsters in your graveyard with different names in your graveyard; attach those targets to this monster as Xyz Material.
● While this card has 4 or more material, it cannot be removed from the field.