Staff of Compleation's third ability by tapping it and paying three life, causing you to put four +1/+1 counters on
Cryptic Trilobite and
Spike Feeder.
Activate
Spike Feeder's second ability twice by removing two +1/+1 counters from it, causing you to gain four life.
Activate
Cryptic Trilobite's first ability three times by removing three +1/+1 counters from it, adding six ({C} magic symbol) that can only be spent to activate abilitieis.
Activate
Staff of Compleation's last ability by paying ({5} magic symbol) , untapping it.
Repeat.
Once you have infinite mana and life, you may activate
Staff of Compleation's other abilities.
Results
Infinite card draw.
Infinite colored mana.
Infinite colorless mana that can only be spent to activate abilities.
Infinite draw triggers.
Infinite lifegain.
Infinite lifegain triggers.
Infinite proliferate.
Infinite +1/+1 counters on most creatures you control.