When Skullwinder enters the battlefield, it and Lonis trigger.
Resolve the Skullwinder trigger, returning Essence Flux from your graveyard to your hand, and causing target opponent to return a card from their graveyard to their hand.
Resolve the Lonis trigger, creating a Food, a Clue, and a Treasure artifact token.
Activate the Treasure by tapping and sacrificing it, adding ({U} magic symbol) .
Repeat.
Results
Infinite Clue tokens.
Infinite ETB.
Infinite Food tokens.
Infinite LTB.
Infinite magecraft triggers.
Infinite storm count.
Target opponent returns all cards in their graveyard to their hand.