Szarekh, Techromancer

Pay 3 life: Assemble 1.
Tap 3 untapped constructs you control: Draw
a card.
Sacrifice another construct: Szarekh,
Techromancer gains Hexproof until end of turn.
You gain life equal to the sacrificed creature's toughness.
{x}{t}: Create a token that's a copy of target
creature with CMC X, except it's an artifact construct in addition to its other types.
X can't be 0.