mtg card database download Magic: The Gathering Printing Custom Magic Card Proxies

I mean this is a really convoluted way to do it

The vast majority of the cards in Mono-Blue are common or uncommon, and it is very easy to accumulate the necessary wild cards to craft cards of that rarity on Magic Arena

Up until now, you only needed your hands and maybe some original cards for reference, but going forward, you may need some tools to help you in the process

Keleth, Sunmane Familiar Keleth, Sunmane Familiar has the Boros condition that requires it to attack, so embrace it and conserve the counters with Reyhan, Last of the Abzan, protect your attacking commander with Ollenbock Escort, and reward the attack with Lae'zel, Vlaakith's Champion

If an effect allows you to spend mana "as though it were mana" of any color or type, that allows you to spend mana you couldn't otherwise spend, but it doesn't change what mana you spent to cast the spell

Mutational Advantage offers a similar effect, but with some interesting pros and cons