The OP-04 Kingdoms of Intrigue Booster Box (Japan) was officially released on September 22, 2023
It gets even better if you build around it by playing spells you especially want to copy, but assuming you are in the right colors, Dualcaster Mage is the first card I'd put in every Naban, Dean of Initiation Commander deck I build
For example, Captured Sunlights cascade trigger would allow you to cast the next nonland card with mana value 0, 1, 2, or 3 from your deck
**Uncommon** Slightly rarer than commons, usually a few per pack
Other than fairly vanilla dorks (Stone Throwing Devils and Tundra Wolves) Naturalize represents a the first colour shifted reprint of a core effect
You can also use equipment artifacts that give any of your creatures this ability, such as Paradise Mantle, which is colorless and taps for any color mana, making it useable in any color deck