Heretek Engineer

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 your end step.) Once you have
4 or more Maintenance counters, create a 4/1 colorless Servitor artifact creature token with
defender and This creature can block up to
two creatures within combat.
{r}: Artifacts creatures you control lose defender
and gain trample until end of turn.