Undercity Sewers [Murders at Karlov Manor] Frog and that player can't activate

and that player can't activate abilities that aren't mana abilities

Set: Magic Origins Type: Enchantment Rarity: Rare Cost: {2}{B} If an opponent would gain life

Convert a Transformers toy you own to its other mode: Grimlock

(You may reveal a Lesson card you own from outside the game and put it into your hand

The chant was incomprehensible

Undercity Sewers [Murders at Karlov Manor] Frog and that player can't activateSet: Murders at Karlov Manor Type: Land Island Swamp Rarity: Rare (T: Add U or B.) Undercity Sewers enters the battlefield tapped. When Undercity Sewers enters the battlefield, surveil 1. (Look at the top card of your library. You may put it into your graveyard.)