The best weapon would be the Scorpion Flail with the Shock Mod in Rachet Gladiator, you slam it into the ground and lightning is sent flying to all the enemies in the area. Too bad the game sucked though.
Worst weapon would be the Black Hole in Megaman V, you had a weapon that could only fly upwards and you would still find more uses for it. The Black Hole was not only pitifully weak it was also slow to connect and you can't do anything while you wait for it to connect so you get owned pretty bad. Not to mention that the boss weak to it being Mercury is able to shoot like five grab busters at you before the Black Hole connects causing you to lose your Super tank and all your energy tanks, you're much better off just using the arm cannon against him. I just hate it when weapons are completely useless but then I hate weapons that have a use but are completely inferior to a default weapon with infinite ammo even more.
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