Mana Crypt

At the beginning of your upkeep, flip a coin. If you lose the flip, Mana Crypt deals 3 damage to you.
{T}: Add {C}{C}.

Taiga

{T}, Pay 1 life, Sacrifice Scalding Tarn: Search your library for an Island or Mountain card, put it onto the battlefield, then shuffle.

{T}, Sacrifice Lotus Petal: Add one mana of any color.

Whenever City of Brass becomes tapped, it deals 1 damage to you.
{T}: Add one mana of any color.

{T}: Add one mana of any color in your commander's color identity.

{T}, Pay 1 life: Add one mana of any color.

Trample
Permanent spells you cast that have an Adventure cost {1} less to cast.

Mill seven cards. Then put all cards that have an Adventure from among the milled cards into your hand.

{T}, Pay 1 life, Sacrifice Wooded Foothills: Search your library for a Mountain or Forest card, put it onto the battlefield, then shuffle.

Whenever you cast an Adventure instant or sorcery spell, copy it. You may choose new targets for the copy.

Whenever you cast a creature spell that has an Adventure, draw a card. (It doesn't need to have gone on the adventure first.)