You push off of the wall and speed through the hole in the wall you created. You enter a hatch in the tungsten sphere, and you see a mess of pipes and cables connected into the ship's fusion reactor. You haven't ever been permitted to maintain the core, that was the mechanic's jobs, but you have had experience changing light bulbs, how different could it be? You find the master cable that splices power out of the turbines, and use your exacto knife to slice off the insulation, leaving the exposed wire. You do the same to the return wire that completes the circuit. You take a wire you ripped out of the armory, unravel it some more, then connect it to the master cable, take another cable and attack it to the return cable. By this point, enemy soldiers were entering the reactor room, trading shots with the few remaining defenders. You take both wires, careful to keep the exposed ends pointed away from each other, crawl through the hatch, and throw both of them towards either side of the blob of enemy's scrambling through the breach. The cables gracefully fly through the room, as the wires unfurl. Right as the wires reach the enemies, the wires run out of length, and the ends snap back towards each other, with the enemies right between them. The result is a blinding bolt of lightning traveling through the vacuum, into the titanium-armored enemies, connecting back to the return wire and completing the circuit.
Just like a light bulb.
After a moment, the two tiny wires you used melt and the current stops. All the lights in the room turn off as the electricity traveled through the enemies, but it turned back on once the wires disintigrate. All the enemies in the circuit were nothing more than red puddles of molten metal and carbon. There were still the last few enemies coming though, it seemed that they were carrying piles of radiation shock grenades, and they were throwing them towards the reactor. The tungsten shell could witshstand a few of them, but even it would melt. These must be the last surviving boarders if they were attempting such suicidal tactics. If you can kill them, then the ship would be safe on the inside!