In general, the icon for a spoiler review would be cool to have a cake outline, referencing "The Cake is a Lie", which in and of itself is so overly famous everyone knows it, kinda like the Darth Vader head icon over on LB.

Another option could be a Sephiroth head outline from FF7, but I felt that spoiler a little more obscure despite the game's fame.

Stars are colored yellow with eyes, to represent power stars

Stars are replaced with Shine Sprites

+ Galaxy 2
Stars are colored in a rainbow gradient, to represent Star Bits

Stars are replaced with Power Moons

+ Minecraft Bedrock
Stars are replaced with pixilated hearts

+ Deltarune
Stars are replaced with pixilated hearts

Stars are replaced with pixilated hearts

Stars are replaced with pixilated hearts, with green tops for strawberries

+ KH 2, 3
Stars are replaced with heart outlines

+ DKC 2, 3, Returns, TF,
Stars are replaced with bananas

+ SMB 2, DLX
Stars are replaced with bananas

Stars are replaced with Sandvich silhouettes

+ Dark Souls series
Stars are replaced with flames, referencing the bonfires

Stars are replaced with yellow rings (get it? bro im such a comedian lmao)

Middle three stars are colored yellow, referencing the results screen after a level cleared

+ Tears of the Kingdom
Played icon is replaced with Sheikah Slate eye design

Closing the tab on this page will reopen the same tab nearby the original tab on your browser, referencing Hades' famous death mechanic

Attempting to backspace out of the page will reopen the same page, referencing how Stanley's quest repeats itself

+ Portal 2
- Stars are replaced with pink hearts, referencing the companion cube

- In your logs page for Portal 1 or 2, hover your mouse over the text for the game title. The "O" in the title will become uppercase [and turn blue for P1 / turn orange for P2]. Click on it to be teleported to the page for the other Portal game respectively.

When creating a new log, you'll receive a notification saying "ADVENTURERS BEWARE: DO NOT BEGIN UNLESS YOU INTEND TO FINISH"

+ any game having to do with Pirates
(you can already see where this is going ;)

Log a play session for the game played on a game console via an OS [ex: PS2 via Windows PC]
You'll receive a notification box saying "You wouldn't download a car, would you?" with Yes and No responses. Selecting No closes the window normally. Selecting Yes opens a YouTube link to the You Are a Pirate song (you know the one).

+ Half-Life engine games

Opening the web console on this page and typing "sv_cheats 1" will spew a bunch of fake code into the console until pulling up a notification box on the page saying "Disconnect: You were kicked for cheating."
Once the notification box is closed, the tab is closed as well.

+ Matrix games

Opening the web console on this page and typing "whiterabbit" will spew a bunch of fake code into the console until pulling up a Matrix code rain website [ex: https://matrix.logic-wire.de/]
Also add the phrase somewhere "Wake Up, Neo"