Not only is this a five-on-one match, but the dynamics of the match greatly favor the team with numbers advantage.
(1) Both Jake and Hotsuma have ways to stun/immobilize the enemy: Jake has his insta-cast Freeze spell (powerful enough to hold a 20-foot dragon in place), and Hotsuma has his special shuriken blitz that stuns. This is game-breaking in a many-vs-one fight. If Lu Seraphim is stunned, then it's open season on him, and he's likely not recovering from that.
(2) Prince has time rewind hax. It's possible that Jake/Hotsuma don't manage to get the jump on Lu Seraphim the first time -- but they get to try again and again. They only need one successful opening assault out of many in order to take the match. Lu Seraphim, on the other hand, has to go perfect in order to win. The odds are stacked against him.
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another place and time, without a great divide, and we could be flying deadly high