Trolls, especially fully grown mountain trolls are notoriously hard beasts to deal with. They possess great strength, magical resistance as well as a reasonable speed and a thick hide that protects them from many dangers.
So it was to no suprise, that when the troll started charging at him, Richard found himself moving on instinct, instead of even thinking clearly.
"Stupefy.. Stupefy, Stupefy,StupefyStupefyStupefy "
Bolts of red magic flew from the tip of Richard's wand as he attacked the intimidating figure, only to bounce off it's thick hide. The troll seemed unaffected by the barrage of spells. If anything he seemed even more infuriated as it locked its sight on the short figure in black robes.
'Oh,sh%t!'
Dodging the sudden attempt at grabbing him, Richard quickly ran to his left, barely escaping the troll as it charged past him like a freight train. The troll , because of its dim-witted nature didn't bother stopping as it ran past him uncontrollably before colliding with the wall with a resounding bang.
Richard quickly ran to the opposite edge of the bathroom in one breath, gaining some distance from the disoriented troll. Then while observing the troll, who shook its head, Richard began to seriously consider his options.
Calming down, he started to reconsider his options. Hexes don't work on trolls because of their magic resistance. He didn't know any powerful charms that could affect it and he doubted that he could use his stone sword to take down the troll before the professor's arrive..or even injure it at all. His original plan was to use the club, but the said club had taken an early leave from the scene due to his own incompetence.
Then glancing at the rubble near his feet, Richard gained clarity, and maybe a possible idea on what to do.
Pointing his wand at the rubble infront of him, he opened his magic circuits. This was his own spell. The rubble floated up, seemingly defying gravity before transforming their shape. The wall of rubble infront of Richard turned into a wall of swords. But he was not done there. The magic circuits for fire and enhancement opened up, marking the hundreds of swords infront of him glow in neon bluish patterns before catching on fire.
The moment the troll turned around, he was not greeted by a scared wizard, but countless swords of all sizes, and a wizard behind them with a nasty grin.
"Wingardium Lev..., no wait lets do this my way" Richard felt a grin form in his face as he commanded the swords." Shoot and kill, SWORD RAIN!"
The swords fell on the troll killing it, easily cutting through the thick hide before burning it from the insides. While Richard simply watched the once terrifying mountain of flesh turn into a silent bonfire.