If you took them away, the way Modern would look would be unrecognisable
(Some effects from cards in previous sets may cause these to transform while on the battlefield, though these effects are unusual.) Double-faced cards haven't changed since the last time we saw them in Innistrad: Crimson Vow
#3 Urza, Lord High Artificer Urza, Lord High Artificer is very clearly a card designed for Modern
Transforming it into Ravager of the Fells can remove creatures
That gap between the idea in your head and the thing in your hands is real, and it's frustrating enough to make most people give up
To determine the total cost of a spell, start with the mana cost or alternative cost you're paying (such as the alternative cost of mutate), add any cost increases, then apply any cost reductions