https://youtu.be/80dglrjMOoM?t=3m7s
so we know from the Skullgirls Apps main story that medici tower is approx 200 stories
that would put it roughly 700 million KG in weight as similar sized buildings are in this ballpark
it flew to the top of the city line to strike a blimp and landed in the ocean we can asume this was a distance of 5 miles as a lowball as New Meridian is shown to be a very large city, with The Medici tower being at the center and the entire town of Little Innsmouth seperating the coast from downtow
gravity would pull it down in 2 seconds
this means it flew 4,000 M/S
KE would be 5,600,000,000,000,000 Joules
or 1.34 Megatons of TNT which is just past the threshold of City Level
Priority: 1 (In Valentines Origin story in the app she is shown to be capable of Damaging Marie, yet was unable to win due to Marie regenerating, Meaning Val's attacks are in the ballpark of this, since Valentine is fodder that most of the other characters can at minimum match, this would apply to all playable characters.)
Verse: Skullgirls
Description: Marie tosses Medici Tower across a city at Hypersonic Speeds