I appreciate that.

Really, anyone can beat Garrett. All you need to do is camp at the portal he came through, and eventually he will run out of fuel if he can't find the other. Quick estimation is that to accelerate to mach 10, or 3,400 m/s, requires (roughly 220000 kilograms if memory serves), 0.01 kg of antimatter assuming no friction, which at that velocity is dumb. At that speed, the plane loses 2 megajoules of energy per second to heat, 7.2 gigajoules in an hour. This is of course, very rough calculation I will refine later, but you can very easily fight him to a winning stalemate