Magical Tinkering

Your Commander is an Artificer in addition
to its other types. Artifact Creatures you control have Modular 1 (This creature enters
the battlefield with a +1/+1 counter. When it
dies you may put any +1/+1 counters it had on target Artifact Creature you control.)
Whenever an Artificer enters the battlefield, put a +1/+1 Counter on each
other Artifact Creature you control.