It's all fun and games until someone gets hurt, and even then it's still only a setback. In the cartoon world of That's All Folks! Injury means very little. This is not to say the consequences can't be severe (ranging from social humiliation to literally exploding), but they are typically temporary. In general, if an Injury does not specify otherwise, it only lasts until the end of that Scene, at which point it is no longer relevant to the plot and forgotten. If you leave the Scene, the Injury stops being relevant, and is no longer affecting you. However, if you return to that Scene before it finishes, it starts affecting you again.
However, some Injuries do have more permanent consequences. If something gives a Lasting Injury, then that Injury remains until the end of the session, unless removed (such as through one of the STEAM Abilities, or through visiting the Doctor). These represent a more narratively significant effect on your character.
When an Injury is removed, any negative effects caused exclusively by it are lost, and you gain access to any positive effects that it prevented you from receiving.
The following list is not necessarily exhaustive, but does include all the most common Injuries. Any Injury not on this list will be accompanied by a description.
Exploded
You have exploded. You are no longer in the Scene, and may not send messages in that channel until a new Scene begins. You may still play in other Scenes, of course, and someone with the relevant Mechanic might unexplode you!
Flattened
It's quite hard to defend yourself when you're as flat as a pancake. You lose the benefits of any Gumption Abilities that you have.
Diced
Flopping about on the floor and cut to pieces. In this state, you cannot gain the benefits of any Mechanics that help you move, and suffer penalties to interact with anything. You can still talk and see normally.
Bonked
A sharp knock to the head has left you confused and probably with a half foot tall bruise. You cannot gain the benefits of any Gorm effects.
Debrained
Your brain having been removed you are dumb as a stump, incapable of articulate use of language and feats of mental gymnastics (or even gentle cerebral stretches).
You cannot gain the benefits of any Wits or STEAM Effects.
Noodle Arms
In your weakened state, you cannot gain the benefits of any Beef Effects.
Winded
You are particularly vulnerable and susceptible to harm. The next Injury you take will become a Lasting Injury.
Humiliated
You may not gain the benefits of any Prestige Effects and NPCs will treat you with scorn and disregard you.
Guiltstricken
Whatever you did, was it really worth it? You lose the ability to engage in any Conflicts, automatically losing any that are forced on you.
Shot
You have been shot. While this initially is only a minor inconvenience, if it happens again within the same Scene, you cannot gain the benefits of any of your positive Mechanics.
Beheaded
Some say the head is important. You cannot gain the benefits of any Cartoon Logic or Writing Conventions that you have, as it takes all of your narrative importance to stay functioning.
Incinerated
You have been reduced to a pile of ash. You are no longer in the Scene, and may not send messages in that channel until a new Scene begins. You may still play in other Scenes, of course, and someone with the relevant Mechanic might un-incinerate you!
Thrown-Out Back
You have been forcibly removed from the Scene, and may not return back to it until after it has been finished, unless this Injury is removed from you before then.
Owie
Hammers, nails and thumbs don’t mix. You lose the ability to interact with any objects in the Scene that require fine motor skills, such as picking up objects, turning door handles, or crafting Items.
Inconsolable
Those floods of tears make it hard for anyone to get through to you. You must ignore any IC advice or information you are given.
Dead
Rather unceremoniously, you have been killed in some manner. Don't worry, it's only temporary. You are no longer in the Scene, and may not send messages in that channel until a new Scene begins. You may still play in other Scenes, of course, and someone with the relevant Mechanic might revive you!
Partial Marshmallow-ification
A big part of your body has been turned into pink, soft, sweet, and tasty marshmallow. You are unable to start a violent Conflict or use an Item in that Scene, although you can still interact with things.
Complete Marshmallow-ification
Your body has entirely been turned into marshmallow. You may not send messages in that channel until a new Scene begins. You may still play in other Scenes, of course, and someone with the relevant Mechanic might unmarshmallow-ify you!