Let me explain what happens below. M-21 is fighting a werewolf and during the fight punches him and sends him flying through multiple buildings. AP wise this is nothing special at all considering his rating when transformed (At least 7-C), however what's interesting is that in the process he melts the buildings (vaporizes them). This happens at High Hypersonic speeds and above.
Therefore, At least High Hypersonic, possibly higher for:
Raizel's first key
Muzaka's first key
Frankenstein's third key
M-21's second key
Reasons:
Raizel by default should be above Frankenstein's first three keys
Muzaka is comparable to Raizel and vice versa
Frankenstein with Dark Spear was going at it against 5 werewolves/nobles with enhancements (personal guards of the First Elder) each of whom should be around the level of the werewolf M-21 was facing. Said werewolf was obviously keeping up with M-21.