>>514587
Breivik shot 69 people on his island, and that nightclub shooting in Paris rendered 89 people dead, but both those were closed environments, making it hard to escape. Otherwise you're right about bombs. A heavier-than-air lethal gas dumped into a subway station or upwind from a big immobile crowd has even more potential, but it's also much harder to pull off for one person.
>>514573
If you actually do it, just please don't go after any innocent people.