Time travel is a tricky thing. For a start you have to avoid changing history and breaking the laws of causalit,y both of which are not things you exactly want to do as they usually result in your potential erasure from existance (see Back To The Future) or an almighty space-time paradox (see Doctor Who). However, there is another danger that is often overlooked when it comes to going for a quick jaunt back in time, which is that you have a high chance of being killed by the locals. When considering where to travel in time to, your best bet is to consult a history book as if it were a weather forcast. "Ok, 1918. The year starts of with some rather heavy war, but that is expected to die down towards the end of the year and in its place there will be a strong front of Spanish Flu. Throughout the year there may be some smatterings of institutionalised racism and sexism along with some sufferage showers. Time travellers are advised to take an umbrella."
So, what happens when superheros from, say, the 1980's get transported back in time to both the Wild West and Ancient Eygpt without having time to consult their handy History Forecast. Well, this is What Were They Thinking, the place where we look at the stupidest, most ill-advised things in comic book history, so what do you think happened?