At the beginning of your upkeep, sacrifice Second Chance and take an extra turn.
Pay {1}{W}{U} and tap Hanna to return Second Chance from your graveyard to your hand.
Cast Second Chance.
Pass the turn.
Repeat.

Infinite turns

Second Chance

Hanna, Ship's Navigator

Activate Coretapper's first ability by tapping it, putting a charge counter on Magistrate's Scepter.
Activate Coretapper's second ability by sacrificing it, putting two charge counters on Magistrate's Scepter.
Activate Magistrate's Scepter's second ability by tapping it and removing three charge counters from it, taking an extra turn after this one.
Activate Hanna by paying {1}{W}{U} and tapping them, returning Coretapper from your graveyard to your hand.
Cast Coretapper by paying {2}.
Repeat each turn.

Coretapper

Magistrate's Scepter

Cast Myr Battlesphere by paying {7}.
Myr Battlesphere enters the battlefield, creating four 1/1 Myr creature tokens.
Activate Ashnod's Altar by sacrificing Myr Battlesphere, adding {2}.
Myr Battlesphere dies, triggering Dross Scorpion, untapping Hanna or any other artifact.
Repeat from step 3 for each of the four Myr creature tokens.
Activate Hanna by paying {3} and tapping it, returning Myr Battlesphere from your graveyard to your hand.
Repeat.

Infinite death triggers

Infinite ETB

Infinite LTB

Infinite sacrifice triggers

Infinite storm count

Infinite untap of artifacts

Infinite mana artifacts you control can produce

Myr Battlesphere

Dross Scorpion

Mycosynth Lattice

Ashnod's Altar

Cast Myr Battlesphere by paying {7}.
Myr Battlesphere enters the battlefield, creating four 1/1 Myr creature tokens.
Activate Krark-Clan Ironworks by sacrificing Myr Battlesphere, adding {2}.
Myr Battlesphere dies, triggering Dross Scorpion, untapping Hanna or any other artifact.
Repeat from step 3 for each of the four Myr creature tokens.
Activate Hanna by paying {3} and tapping it, returning Myr Battlesphere from your graveyard to your hand.
Repeat.

Krark-Clan Ironworks

Cast Myr Battlesphere by paying {7}.
Myr Battlesphere enters the battlefield, creating four 1/1 Myr creature tokens.
Activate Ashnod's Altar by sacrificing Myr Battlesphere, adding {2}.
Myr Battlesphere dies, triggering Hanna, untapping Hanna.
Repeat from step 3 for each of the four Myr creature tokens.
Activate Hanna by paying {3} and tapping it, returning Myr Battlesphere from your graveyard to your hand.
Repeat.

Thornbite Staff

Chromatic Orrery

Cast Myr Battlesphere by paying {7}.
Myr Battlesphere enters the battlefield, creating four 1/1 Myr creature tokens.
Activate Krark-Clan Ironworks by sacrificing Myr Battlesphere, adding {2}.
Myr Battlesphere dies, triggering Hanna, untapping Hanna.
Repeat from step 3 for each of the four Myr creature tokens.
Activate Hanna by paying {3} and tapping it, returning Myr Battlesphere from your graveyard to your hand.
Repeat.

Combos with "Hanna, Ship's Navigator"