Yenna, Redtooth Regent | Second Wind | Clever Impersonator

(and one other card)

Creature that taps for 2+ mana

All permanents on the battlefield (
Yenna and Creature that taps for 2+ mana without summoning sickness and
Clever Impersonator not copying anything).

Activate the mana-producing creature by tapping it, adding at least ({2} magic symbol) .
Activate
Yenna by paying ({2} magic symbol) and tapping it, creating a token copy of
Clever Impersonator. Choose to have
Clever Impersonator enter the battlefield as a copy of
Second Wind attached to the mana-producing creature. Then, untap
Yenna and scry 2.
Activate the
Second Wind token's second ability by tapping it, untapping the mana-producing creature.
Repeat.

Because
Clever Impersonator has base toughness of 0, you will need some way to keep it from dying. This can be done using anthem effects, causing it to enter with +1/+1 counters, having Auras attached to it, etc. If the creature being tapped for mana can add ({3} magic symbol) or more, this combo will net infinite mana of those color(s) and type(s).