The Ever-Changing 'Dane

{1}, Sacrifice another creature: The Ever-Changing 'Dane becomes a copy of the sacrificed creature, except it has this ability.

Queza, Augur of Agonies

Whenever you draw a card, target opponent loses 1 life and you gain 1 life.

Tawnos, Solemn Survivor

{2}, {T}: Create a token that's a copy of up to one target artifact token you control. Mill two cards.
{1}{W}{U}{B}, {T}, Sacrifice two artifact tokens, Exile an artifact or creature card from your graveyard: Create a token that's a copy of the exiled card, except it's an artifact in addition to its other types. Activate only as a sorcery.