Forbidden
Ring of destruction- I feel like even with the erratum it's still too good, but who knows
Royal Magical Library- Chicken Race 0.0
Lavalval chain- Random, but keep in mind he can send ANY card to the graveyard and foolish burial is at 1. Granted even in a rank 4 spam deck, it takes a bit more effort than just "I play this 1 card and do this". The stacking effect is just icing. No one realistically plays more than 1 so to 1 wouldn't do anything.
El-Shaddoll Construct- Just to follow ocg and to kill off the deck; it's old and konami doesn't want people playing it anymore xD
Stellarnova Alpha- Or to 1
Heroic Challenger - Thousand Blades- Well he puts gorz to shame, which they gladly put back at 3 for us. Again, you don't really need more than 1 thousand blades unless you're using it for the heroic spam into number 86 effect.
Limited
Imperial Iron Wall- Side deck card that wins against infernoids and ritual beasts, and stops trish.
Stellarknight Triverr- Tellars won't do anything without Triverr spam and it is about that time Konami kills off this deck.
Peropero cerperus- well it might not get hit since people aren't using lightsworn a whole lot aside from infernoids. I've seen this in Shaddolls too though.
Summoner's Art- They won't hit lose a turn so Qlis gotta lose something else.
Manju- Just manju, he searches more stuff
Nekroz of Valkyrus- Either this to 1, brio to 1 and this to 2, or unicore to 1 and this to 2 but it might be overkill if they do hit manju to 1.
Dante, Cir, Graff or fire lake- Just hit 1 to 1
Tribe-infecting virus- personally I think it could be fine at 3, but to 1 just to start would be fine.
Cyber-stein- Same as tribe, nowadays there's veiler, fiendish chain, breakthrough skill, chalice, etc. How happy are you gonna be when you pay 5,000 life points for nothing?
Yata-garasu- Enough decks should have cards that let them search so they can advance their game state even if they get yata'd (nekroz, infernoids, ritual beast spamming ulti-canna). Essentially it would take player A with yata to clear the opponent's board twice before they've won.
Mind master- same as tribe
Thousand-eyes restrict- same as tribe, just keep metamorphisis banned since rank 4 decks will use that to get out norden
Heavy storm- At 1 should be perfect
Future Fusion- this could be the sacky card of the format. Or they can errata it to banish from the deck instead of sending to the graveyard.
Mask Change- This just means heroes would need to run 3 mask charge. And of course Shadow mists will be seeing the graveyard more often than the field.
Solemn Judgment- to counter heavy storm if they do unban it.
Semi-limited
Bottomless Trap Hole- Won't make too much of a difference.
Traptrix trap hole nightmare- With enough use, probably to 1, most people probably only use 2 nowadays anyways
Neo-spacian grand mole
Unlimited
Tragoedia- Gorz was
Necroface- Toons need it I guess?
Card trooper- for noids
Sacred sword of seven stars- red-eyes
Thunder King Rai-oh
Monster gate- noids