Dragonshift

To determine the total cost of a spell, start with the mana cost or alternative cost you're paying (such as an overload cost), add any cost increases, then apply any cost reductions. The mana value of the spell remains unchanged, no matter what the total cost to cast it was.

If you are instructed to cast a spell with overload "without paying its mana cost," you can't choose to pay its overload cost instead.

If you don't pay the overload cost of a spell with overload, that spell will have a single target. If you pay the overload cost, the spell won't have any targets.

Because a spell with overload doesn't target when its overload cost is paid, it may affect permanents with hexproof or with protection from the appropriate color.

Each affected creature will lose any abilities it may have gained prior to Dragonshift resolving. Notably, this includes the ability to cast the copies of a card with cipher that's encoded on the creature, although that ability will return after the turn ends.

If you cast Dragonshift using overload, only creatures you control when it resolves will be affected. Creatures that come under your control later in the turn will not.