Riverchurn Monument

Ward 2 Whenever this creature attacks while saddled, search your library for a nonland permanent card with mana value 3 or less, put it onto the battlefield, then shuffle. Saddle 4

Start your engines! (If you have no speed, it starts at 1. It increases once on each of your turns when an opponent loses life. Max speed is 4.) This creature enters tapped. Max speed — B, Sacrifice another creature or Vehicle: Draw a card.

When this Vehicle enters, create a 1/1 colorless Thopter artifact creature token with flying. Crew 1 (Tap any number of creatures you control with total power 1 or more: This Vehicle becomes an artifact creature until end of turn.)

As Mimeoplasm enters, exile up to X creature cards from your graveyard. It enters with three +1/+1 counters on it for each creature card exiled this way. 2: Mimeoplasm becomes a copy of target creature card exiled with it, except it's 0/0 and has this ability.

Start your engines! When this creature enters, target opponent reveals their hand. You choose an instant or sorcery card from it. That player discards that card. Max speed — This creature gets +1/+1 and has menace.

Start your engines! (If you have no speed, it starts at 1. It increases once on each of your turns when an opponent loses life. Max speed is 4.) When this enchantment enters, it deals 5 damage to up to one target creature or planeswalker. 2, Sacrifice this enchantment: It deals 2 damage to each player who doesn't have max speed.

Menace, deathtouch When this creature enters, put target creature card with mana value 4 or less from a graveyard onto the battlefield under your control with a finality counter on it. That creature gains menace, deathtouch, and haste. At the beginning of your next end step, exile that creature.