Yes, another custom deck I'm working on! I've already realized that the way Poison Joke worked was stupid, so thanks in advance for all your help! XD

Environment
The Everfree Forest

Castle of the Two Sisters (Structure): Reduce damage dealt by Monsters by 1. At the end of the environment turn, play the top card of the villain deck. At the start of the environment turn, all players may discard 1 card to destroy this card.

Zecora's Hut (Structure): At the end of the environment turn, play the top card of the environment deck. At the start of the environment turn, all hero targets may regain 1 HP each. If no hero targets regain HP this way, destroy this card.

(2) Manticore (Monster, 10 HP): At the end of the environment turn, this card deals the hero target with the highest HP 3 melee damage. Then it deals the hero target with the highest HP 2 toxic damage.

Cockatrice (Monster, 4 HP): At the end of the environment turn, this card deals the hero target with the lowest HP 1 psychic damage. A hero taking damage this way may not play cards or use powers until the start of the environment turn.

River Serpent (Monster, 14 HP): This card cannot be damaged by hero targets. At the start of the environment turn, one hero may draw a card. At the end of the environment turn, the environment target with the highest HP deals this card 2 cold damage.

The Shadowbolts (Monster, 5 HP): At the end of the environment turn, this card deals the X hero targets with the highest HP 2 sonic damage each, where X is the current HP of this card.

The Ghostly: Players may not draw cards. At the start of the environment turn, one player may discard their hand to destroy this card.

Crumbling Cliff: When this card enters play, each hero must discard 2 cards or take 2 melee damage. At the end of the environment turn, destroy this card.

The Animals Take Care of Themselves: At the end of the environment turn, all environment targets heal 2 HP. At the start of the environment turn, all players may shuffle their trash into their deck to destroy this card.

The Plants Grow All on Their Own: At the end of the environment turn, search the environment deck and trash until a Monster card is found and put it into play, then shuffle the environment trash into the environment deck. At the start of the environment turn, each player may destroy any number of ongoing or equipment cards. If (H) cards are destroyed this way, destroy this card.

The Clouds Move: At the end of the environment turn, this card deals all targets 1 lightning damage. At the start of the environment turn, place this card on the bottom of the environment deck.

(2) Timberwolves (Monster, 6 HP): At the end of the environment turn, this card deals the (H)-1 hero targets with the lowest HP X melee damage each, where X is the number of Monsters in play.

Poison Joke: At the end of the environment turn, each player must discard a card or the environment deals that hero 2 toxic damage. Heroes' innate powers are replaced by the power of the hero directly before them in turn order.