Sorcerer's Broom | Ashnod's Altar | Stridehangar Automaton

Cards

Use
Ashnod's Altar to sacrifice another creature, or sacrifice a permanent by any other method.
Sorcerer's Broom triggers, causing you to pay ({3} magic symbol) to create two creature tokens due to
Stridehangar Automaton.
Activate
Ashnod's Altar twice by sacrificing the
Sorcerer's Broom tokens, adding ({C} magic symbol) ({C} magic symbol) ({C} magic symbol) ({C} magic symbol) .
Sorcerer's Broom triggers twice, and each
Sorcerer's Broom token triggers once.
Resolve all but one trigger, choosing not to pay.
Resolve the final trigger, causing you to pay ({3} magic symbol) to create two creature tokens.
Repeat from step 3.

If you sacrifice a creature to start using
Ashnod's Altar, the starting cost is reduced to ({1} magic symbol) . You can instead use a permanent that can sacrifice itself (like a Treasure token) or another method to sacrifice a permanent (like Braids, Arisen Nightmare).

This combo has been estimated to be Exhibition (Bracket 1+).