Skitarii Vanguard

Canticle (You may tap this creature. If you do, you
gain 1 counter of Maintenance, then trigger any
relevant Canticle effects. All counters of Maintenance
are sacrificed during the end step.)
Once you have 2 or more Maintenance counters,
scry 1.
{4}{u}{u}: Draw a card. This abilty costs {1} less for
every other artifact creature you control.