Clockwork Swarm
{4}
Artifact Creature -- Insect
0/3
~this~ enters with four +1/+0 counters on it.
~this~ can't be blocked by Walls.
At end of combat, if ~this~ attacked or blocked this combat, remove a +1/+0 counter from it.
{X}, {T}: Put up to X +1/+0 counters on ~this~. This ability can't cause the total number of +1/+0 counters on ~this~ to be greater than four. Activate only during your upkeep.
Juggernaut
{4}
Artifact Creature -- Juggernaut
5/3
~this~ attacks each combat if able.
~this~ can't be blocked by Walls.
Otarian Juggernaut
{4}
Artifact Creature -- Juggernaut
2/3
~this~ can't be blocked by Walls.
Threshold -- As long as seven or more cards are in your graveyard, ~this~ gets +3/+0 and attacks each combat if able.