March of the Machines

First strike (This creature deals combat damage before creatures without first strike.) When this creature enters, you gain 1 life for each card in your graveyard.

First strike (This creature deals combat damage before creatures without first strike.) When this creature enters, you gain 1 life for each card in your graveyard.

Flying When this creature enters, you gain 3 life.

Flying When this creature enters, you gain 3 life.

Target creature gets +3/+3 and gains flying until end of turn. (It can't be blocked except by creatures with flying or reach.)

Target creature gets +3/+3 and gains flying until end of turn. (It can't be blocked except by creatures with flying or reach.)

Whenever a creature you control enters, you gain life equal to its toughness.

Defender (This creature can't attack.) Flying