Helga, Skittish Seer + Chakram Retriever + Hoverguard Sweepers Combo

Hoverguard Sweepers in hand.

Helga and Chakram Retriever on the battlefield.

Helga has power 8 or greater and does not have summoning sickness.

Activate Helga by tapping it, adding at least eight that can only be spent to cast creature spell with mana value 4 or greater or with in their mana cost.

Cast Hoverguard Sweepers 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 Hoverguard Sweepers enters the battlefield, it triggers, returning it and up to one other creature from the battlefield to their owner's hand.

Repeat.

Infinite card draw

Significant lifegain

Significant lifegain triggers

Significant creature ETB

Infinite draw triggers

Significant storm count

Significant creature LTB

Significant +1/+1 counters on a creature

Significant 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

Return a portion of target creatures to their owner's hand