Sure there are some raids that stand out due to their main target being civilians/morale, for example Dresden or the London Blitz. But the other 360 days of the year these bombers were flying with their bombs aimed against industrial targets like factories, dams, ball-bearing plants, powerplants, railstations, bridges or oil/synthetic refineries.
These other raids achieved much more practical war results then the terror bombing ever did, but since they were less controversial and less deadly they are not heard about nearly as much.
In HoI games all strategic bombing is the raids on these legitimate war targets which is over 90% of what was done in reality as well.
For the most part when you read in the history books about "the bombers were bombing city X" their main targets was the factories producing war critical material in the suburbs of city X. Both Allies and Axis learned from the London Blitz that terror bombing didn't really work and only strengthened the civilian resolve and fighting spirit instead of lowering in as intended.
Anyways as others have already pointed terror bombing is also against the forum rules to discuss and never will be in a HoI game, and I'm pretty sure that biological warfare also falls under these same rules.