A foundational characteristic of any roleplay is its tone. At least that's my position, and I imagine most roleplayers would agree with me. Yet, in my experience, it's a world/setting element rarely discussed on roleplay forums. Some of the fault may be due to how we commonly categorize roleplays. We generally group them loosely by genre: scifi, fantasy, modern slice of life, etc. Occasionally we go deeper and identify their subgenre: fantasy magical academy, post apocalyptic nation builder, 1940s mob thriller, and so on. And while identifying your genre and subgenre are generally helpful - as it provides quick setting & story information - the often unidentified tone of your world can be more important (a stronger deciding factor) to perspective players than either your genre or subgenre. The following is an example of a setting with an identical genre but with significant tonal difference. The above is artwork for Batman The Animated Series. It's, quite obviously, set in Gotham with a classic Bat-Family cast. The world's tone is a combination of cartoonish mystery, pulp adventure, larger than life characters, and conflicts that resolve with the "good guys" always managing to pull out a victory. In contrast to BTAS the above artwork, for the animated Batman film Under the Red Hood, is also set in Gotham. But in its crime-ridden iconic city, the dangers are much greater. It's brutal. It's miserable. It's a place that chews both heroes and villains and spits them back out. Here victory for the "good guys" (if you can find any) may be out of reach. Here the people the Bat-family hope to save may actually not survive. Speaking for myself I appreciate both tones. Each has its merits and limitations, and neither is objectively greater than the other. But while they have identical setting pieces at a glance, at their heart they're night and day. The two worlds and characters should not intermingle, less the setting's tone (spirit imo) be compromised. I Am Not Suggesting Roleplay Tones Don't Have Ranges Every roleplay, no matter the tone, has a range of moods, emotions, and situations that it can comfortably support. For example, a 1940s organized crime roleplay that has the look and feel of The Godfather, can support its share of lighthearted and heartwarming scenes and characters. But they need to be used and executed carefully. Because a tipping point can easily be reached where the original tone of the roleplay is transformed into something new. In our mob thriller example, introducing a cartoonish gangster can quickly make the tone feel closer to Dick Tracey as opposed to The Godfather. Which is often (and understandably) upsetting to some of your players. But Do Players Not Have The Right To Alter A Roleplay's Tone? Not in my opinion. That would be narrative bait and switch. And the other players expect the tone to be maintained. In the same way they reasonably expect worlds without magic to never have magic smuggled in. GMs Should Protect Their Tone Here's where it gets interesting. It's common for GMs to make sure character applications are of the appropriate genre for their setting, but in my experience, less common for them to correct tonal issues. An elven sorceress is an elven sorceress, right? Wrong. In the same way that a Batman villain is not just a Batman villain. Their tone—their presentation and setting fit, matters. I believe countless RPs have been poisoned to death by this narrative crime. A character is introduced who doesn't belong, other players silently resent and reject them, and they begin to look for a way out if the offending party stays on. With all of the above in mind, I suggest players and GMs maintain and reinforce the tone of the roleplays they participate in. If you ignore the kazoo in your jazz ensemble you might just lose your audience.