Deaddy Bears

[Toffee.]

Deaddy Bear - Forgotten Playmate
DARK / Level 4
[Beast/Effect]
During the opponent's turn, you can equip this card from your hand to 1 Face-up monster your opponent controls. You must control a Face-up "Deaddy Bear" monster OR control a monster that is owned by your opponent to activate and resolve this effect. 1 monster can only be equipped with 1 "Deaddy Bear" monster at a time. The ATK and DEF of a monster equipped with this card become 0. If either the equipped monster is removed from the field or used as an Xyz Material and this card is sent to the Graveyard, OR this card is destroyed by your opponent's card effect: Special Summon 1 "Deaddy Bear" monster from your Deck.
ATK 1000 / DEF 0

Deaddy Bear - Unloved Heart
DARK / Level 4
[Beast/Effect]
During the opponent's turn, you can equip this card from your hand to 1 Face-up monster your opponent controls. You must control a Face-up "Deaddy Bear" monster OR control a monster that is owned by your opponent to activate and resolve this effect. 1 monster can only be equipped with 1 "Deaddy Bear" monster at a time. The ATK and DEF of a monster equipped with this card become 0. If either the equipped monster is removed from the field or used as an Xyz Material and this card is sent to the Graveyard, OR this card is destroyed by your opponent's card effect: Add to your hand 1 "Deaddy Bear" monster from your Deck, except "Deaddy Bear - Unloved Heart".
ATK 1000 / DEF 0

Deaddy Bear - Empty Childhood
DARK / Level 4
[Beast/Effect]
During the opponent's turn, you can equip this card from your hand to 1 Face-up monster your opponent controls. You must control a Face-up "Deaddy Bear" monster OR control a monster that is owned by your opponent to activate and resolve this effect. 1 monster can only be equipped with 1 "Deaddy Bear" monster at a time. The ATK and DEF of a monster equipped with this card become 0. If either the equipped monster is removed from the field or used as an Xyz Material and this card is sent to the Graveyard, OR this card is destroyed by your opponent's card effect, You can target 1 Spell/Trap card on the field: Send it to the Graveyard, and if you do, Draw 1 card.
ATK 1000 / DEF 0

Deaddy Bear - Abandoned Soul
DARK / Level 4
[Beast/Effect]
During the opponent's turn, you can equip this card from your hand to 1 Face-up monster your opponent controls. You must control a Face-up "Deaddy Bear" monster OR control a monster that is owned by your opponent to activate and resolve this effect. 1 monster can only be equipped with 1 "Deaddy Bear" monster at a time. The ATK and DEF of a monster equipped with this card become 0. If either the equipped monster is removed from the field or used as an Xyz Material and this card is sent to the Graveyard, OR this card is destroyed by your opponent's card effect, Target 1 "Deaddy Bear" monster in your Graveyard, except "Deaddy Bear - Abandoned Soul": Either add it to your hand or Special Summon it,
ATK 1000 / DEF 0

Deaddy Bear - Sorrowful Tears
DARK / Level 4
[Beast/Effect]
During the opponent's turn, you can equip this card from your hand to 1 Face-up monster your opponent controls. You must control a Face-up "Deaddy Bear" monster OR control a monster that is owned by your opponent to activate and resolve this effect. 1 monster can only be equipped with 1 "Deaddy Bear" monster at a time. The ATK and DEF of a monster equipped with this card become 0. If either the equipped monster is removed from the field or used as an Xyz Material and this card is sent to the Graveyard, OR this card is destroyed by your opponent's card effect: Gain 3000 Life Points.
ATK 1000 / DEF 0

Deaddy Bear - Un-Hugable
DARK / Rank 4
[Beast/Xyz/Effect]
3 Level 4 DARK monsters.
If you currently control a monster(s) that is owned by your opponent, you can Xyz Summon this card with 1 (only) less Xyz Material if you use 1 of those monster(s) as an Xyz Material. When this card is Xyz Summoned, add to your hand up to 2 "Deaddy Bear" monsters from your Deck or Graveyard. Once per turn: You can Draw 1 card for each monster you control that is owned by your opponent. Then, send all other monsters you control to the Graveyard. This card cannot attack the turn you activated this effect. If this card destroys an opponent's monster by battle, the opponent cannot Set any cards during his/her next turn. Once per turn, during either player's turn: You can pay half your Life Points, and if you do, Banish this card. Then, during your next Standby Phase, return this card to your side of the field.
ATK 2500 / DEF 0

Forgotten Toybox
Spell / Field
Once per turn: You can pay half your Life Points, and if you do, gain control of all monsters your opponent currently controls that are equipped with a "Deaddy Bear" monster. Then, send all "Deaddy Bear" monsters in your Spell/Trap card zones to the Graveyard. Then, and for as long as you control them, the monsters who's control was switched by this effect are treated as DARK, their effect(s) are negated, and the ATK of each of those monsters becomes 1000. If this card is removed from the field, return control of all Face-up monsters currently on the field to their original owners.

Inside the Toybox
Spell / Quick-Play
Pay 1000 Life Points: Activate 1 "Forgotten Toybox" from your hand, Deck, or Graveyard.

Life in the Toybox
Spell
You can only activate this card during your Main Phase 1. Send 1 monster you control that is owned by your opponent to the Graveyard: Draw 3 cards. You can only activate 1 "Life in the Toybox" per turn. You must control a "Forgotten Toybox" to activate and resolve this effect.

Stitched Together
Spell
Banish 1 "Deaddy Bear" monster in your Graveyard: Special Summon 1 Level 4 "Deaddy Bear" monster from your hand or Graveyard.

Deaddy Bear Memories
Trap
Add to your hand 1 "Deaddy Bear" monster from your Deck. You cannot Summon/Set or activate any effect(s) of that monster during this turn.

Deaddy Bear Play Time
Trap
Equip 1 "Deaddy Bear" monster from your Graveyard to a Face-up monster your opponent controls.

Deaddy Bear Lost Affection
Trap
Target 1 monster your opponent currently controls that is equipped with a "Deaddy Bear" monster: Destroy it, and if you do, Gain 2000 Life Points.

Patchwork
Trap
Discard 1 "Deaddy Bear" monster, and if you do, Special Summon 1 "Deaddy Bear" monster from your Deck. Then, you can Target 1 Face-up monster the opponent controls: It's ATK becomes 0. You can only activate 1 "Patchwork" per turn.

[Lonk]

This archtype is interesting and full of feels.  It may have some steep life costs, but deaddy bears also tend to restore them back, so they aren't really that steep.  I also love the design on Forgotten Toybox.

[Toffee.]

This archtype is interesting and full of feels.  It may have some steep life costs, but deaddy bears also tend to restore them back, so they aren't really that steep.  I also love the design on Forgotten Toybox.

Technically, because of the fact your always putting your opponent's monsters to 0 ATK/DEF, the Life Point costs aren't that much of an issue because I doubt they could ever get a solid attack in.