cheese- time loves bubbles, this is a time displacement bubble from the traveling the creature has done, when it contacts something from the present, it creates a time bubble.
ot- the more i think about it, the more im not sure if aiming to hit either sweet spot would be the best way to form this cards atk and subsequent cost, i think the priority would be putting it into a vacant range within time's creatures. this would basically mean something in the 4-7 damage range, and given the cost of vampires, both costs are atk+1, with the upgraded receiving +3 damage, but given the mono-synergy with nightfall, something time doesnt have, i think there can be a little flexibility in terms of generating an atk/cost ratio. alternatively, the phoenix/abom model may be used, with the basic creature being a higher cost, higher damage, worse ratio creature than the upgraded.