Gonti's Aether Heart | Prototype Portal | Lithoform Engine

(and one other card)

Activate
Prototype Portal by paying ({6} magic symbol) and tapping it.
Holding priority, activate
Lithoform Engine's first ability by paying ({2} magic symbol) and tapping it, copying
Prototype Portal's ability.
Resolve the copy of
Prototype Portal's ability, creating a token copy of
Gonti's Aether Heart.
When the
Gonti's Aether Heart token enters the battlefield, it triggers twice, causing you to get ({E} magic symbol) ({E} magic symbol) ({E} magic symbol) ({E} magic symbol) .
Resolve the original
Prototype Portal ability, creating a token copy of
Gonti's Aether Heart.
Put either
Gonti's Aether Heart token into your graveyard due to the legend rule.
When the
Gonti's Aether Heart token enters the battlefield, it triggers twice, causing you to get ({E} magic symbol) ({E} magic symbol) ({E} magic symbol) ({E} magic symbol) .
Activate the remaining
Gonti's Aether Heart token by paying eight ({E} magic symbol) and exiling it, causing you to take an extra turn after this one.
Repeat each turn.