Helga has power 4 or greater and does not have summoning sickness.
Steps
Activate Helga by tapping it, adding at least four mana of any color that can only be spent to cast creature spell with mana value 4 or greater or with ({X} magic symbol) in their mana cost.
Cast Ancestral Statue by paying its mana cost.
Helga and Chakram Retriever trigger.
Resolve the Helga trigger, causing you to draw a card, gain 1 life, and put a +1/+1 counter on Helga.
Resolve the Chakram Retriever trigger, causing you to untap Helga.
When Ancestral Statue enters the battlefield, it triggers, returning it from the battlefield to your hand.
Repeat.
Results
Infinite card draw.
Near-infinite lifegain.
Near-infinite lifegain triggers.
Near-infinite ETB.
Infinite draw triggers.
Near-infinite storm count.
Near-infinite LTB.
Near-infinite +1/+1 counters on Helga.
Near-infinite colored mana that can only be spent to cast creature spells with mana value 4 or greater or creature spells with X in their mana cost.