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
I mean this is a really convoluted way to do it
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
And before that, the Lord of the Rings set was good fun, with great art and fascinating mechanics
Just to start, it can be a bit of a theft deck and a bit of a typal deck with some manifest synergies thrown in for good measure
Captain Lannery Storm's last ability triggers whenever you sacrifice a Treasure for any reason, not just to activate a Treasure's mana ability