Phyrexian Dreadnought

Trample
When Phyrexian Dreadnought enters, sacrifice it unless you sacrifice any number of creatures with total power 12 or greater.

Varolz, the Scar-Striped

Each creature card in your graveyard has scavenge. The scavenge cost is equal to its mana cost. (Exile a creature card from your graveyard and pay its mana cost: Put a number of +1/+1 counters equal to that card's power on target creature. Scavenge only as a sorcery.)
Sacrifice another creature: Regenerate Varolz, the Scar-Striped.

Traverse the Ulvenwald

Search your library for a basic land card, reveal it, put it into your hand, then shuffle.
Delirium — If there are four or more card types among cards in your graveyard, instead search your library for a creature or land card, reveal it, put it into your hand, then shuffle.

Gitaxian Probe

({U/P} can be paid with either {U} or 2 life.)
Look at target player's hand.
Draw a card.