Cast Capture of Jingzhou by paying {3}{U}{U}, granting you an extra turn after this one.
Cast Mystic Reflection by paying {1}{U}, causing the next creatures or planeswalkers to enter the battlefield this turn to enter as copies of Archaeomancer.
Cast From Under the Floorboards by paying {3}{B}{B}, creating three token copies of Archaeomancer and gaining 3 life.
Each of the Archaeomancer's ETBs trigger, returning Mystic Reflection, Capture of Jingzhou, and From Under the Floorboards to your hand.
Repeat.

Infinite turns

Lock

Archaeomancer

Mystic Reflection

Capture of Jingzhou

From Under the Floorboards

Cast Temporal Manipulation by paying {3}{U}{U}, granting you an extra turn after this one.
Cast Mystic Reflection by paying {1}{U}, causing the next creatures or planeswalkers to enter the battlefield this turn to enter as copies of Archaeomancer.
Cast From Under the Floorboards by paying {3}{B}{B}, creating three token copies of Archaeomancer and gaining 3 life.
Each of the Archaeomancer's ETBs trigger, returning Mystic Reflection, Temporal Manipulation, and From Under the Floorboards to your hand.
Repeat.

Temporal Manipulation

Cast Time Warp by paying {3}{U}{U}, granting you an extra turn after this one.
Cast Mystic Reflection by paying {1}{U}, causing the next creatures or planeswalkers to enter the battlefield this turn to enter as copies of Archaeomancer.
Cast From Under the Floorboards by paying {3}{B}{B}, creating three token copies of Archaeomancer and gaining 3 life.
Each of the Archaeomancer's ETBs trigger, returning Mystic Reflection, Time Warp, and From Under the Floorboards to your hand.
Repeat.

Combos with "From Under the Floorboards"