Charge of the Titans

You charge forward with a surge of magical speed and size. Your movement speed is doubled, and every 10ft you move, your scale increases by 1 in every dimension. Ex, if you move 20ft your character has now grown by a scale of 3 in every dimension. The equation for scale (ft moved [rounded down to the nearest 10] /10 + 1). Be careful though, nothing but your clothes scale with you, so you can't use items while enlarged, which means you can only use unarmed strikes to deal damage, but your unarmed strike damage scales with you. Your unarmed strikes now deal 1d8 + your strength mod, per scale increase. Ex, you move 30ft and your strength mod is +3, you deal 3d8 + 9 damage.