No, you cant use colorless mana for any color, as colorless mana can only pay for generic costs or specific colorless requirements
Ian Malcom Secret Lair, Reddit user AttilatheFun87 revealed that the package contained a card that had not been announced alongside the others, as is often the case with Secret Lair
Lorthos will require a big commitment to mana, but we get a three hit Commander Kill, so that has some game winning there that hopefully can play with the other three brews
Most sets have a draft common common or uncommon that can repeatedly inflict one damage on each opponent just by playing other cards, like Firebrand Archer or Erebor Flamesmith
This is definitely an odd card, but the ability to counter black spells indefinitely, as long as you have the mana, still stacks up as quite strong