Low cost commanders such as Rhys, the RedeemedRhys, the Redeemed, Emmara, Soul of the AccordEmmara, Soul of the Accord, or Temmet, Vizier of NaktamunTemmet, Vizier of Naktamun get extra mileage from these effects, as casting them multiple times in a game is likely to happen
You can change the numeral inside of a mana symbol, but you can't modify the cost of a spell in time to pay less for it
We had a box of Pokemon Cards and needed help assessing their value so we would know what to do with them The guy at this place was a walking Pokemon Card Encyclopedia, educated us on card values, shared the card selling market dynamics and made us a fair price offer on the entire box
Lets speculate as wildly as we possibly can
It can also transform for the low cost of a single red mana, assuming you play three or more instants or sorceries that turn