Sad Spongebob

stanley's suicide

For me it’s Ashi’s fate, Gary come home, Fern’s death, Phil dying

When Phineas didn't know what to do today

when rue died

when atla was over

Tom & Jerry's suicide.

not a thing, no way

Its canon

hold on

Remember the episode where they sat on the train track all sad and depressed? Yeah, the train was coming their way, they were waiting for it.

Goku, Tony Stark, And Zane (Ninjago)

I personally think it’s the ending of that burrito episode from We Bare Bears. as well as in Avatar when Iroh was singing for his deceased son.

Hopper's letter in Stranger Things 3
When Clone Wars ended
Darth Vader vs Ahsoka in Rebels
The forced suicide in Lost In Space