For those who don't know Tainted Treasure Rooms,here's a link to the it:
https://steamhost.cn/steamcommunity_com/sharedfiles/filedetails/?id=2818356312

I've come up with ideas for Tainted counterparts of items from your mods!
Blood of the Void(Blood of the Abyss):“Tastes sinister” Turns all red hearts & soul hearts into black hearts upon pickup. Grants 3 shields per floor. These shields spawn 2-5 shadow maggots when one breaks.
Enraged Concussion(Concussion):“Super Stunner” Taking contact enemy damage triggers Concussion,pushes back enemies around you and inflicts confusion on them!
Charred Placard(Stolen Placard): “Tainted advertisements” Items it spawns come from the Tainted Treasure rooms item pool instead of the current room’s item pool.
Reversed Abundance(Abundance): “A Price for Possessions” Items in shops cost 2.5x the amount,but one of the following 'good' events is triggered.

• No Curses!:Removes all curse effects in the floor
  
• Free Credit!:Credit Card effect
  
• Greedy Buddies:Spawns a friendly Greed gaper from each shopkeeper in a shop
  
• Helping Hand!:Grants Strawman!
  
• Free Membership!:Spawns a trapdoor to the Secret shop,cannot if he has a member card or if player is in a Secret shop
  
• Free Gold!:Spawns an item the Fancy Brooch’s item pool!

Silver Flakes(Flakes of Gold): “Shockingly edible!” Spawns 1-2 quicksilver hearts on pickup. Gold hearts have a chance to be quicksilver hearts,and losing one can petrify enemies and shock them!
Quake Stone Bar(Quake Oats):“Bitter Crunch” Retains Quake Oats’ passive effect,taking damage triggers the active effect.
Veil of Light(Veil of Darkness):“Bright-White Enlightenment” On pickup,+1 eternal heart,grants an item from its own light-related item pool,and with this item,active curses grant random stat boosts! Examples are Angelic Prism,Night Light,Holy Light,etc.

What do you say,Preyn? Do you wanna make this big idea of mine a reality?