Activate Mirror Entity by paying ({1} magic symbol) , causing all creatures you control to have base power and toughness 1/1 and gain all creatures types until end of turn.
Activate Battered Golem by paying ({R} magic symbol) and tapping it.
Magda triggers, creating a Treasure artifact token.
When the Treasure enters the battlefield, Battered Golem triggers, untapping itself.
Resolve the Battered Golem ability from step 1, dealing 1 damage to any target.
Activate the Treasure by tapping and sacrificing it, adding ({R} magic symbol) .