The Hot/Cold Scam is a common Scam used mainly at the Grand Exchange. It's actually a very simple and easily done scam. The scammer would constantly say "Hot/Cold x2", where the scammer would use a Mithril Seed on the ground and see what flower comes up. The victim would choose either hot or cold (Hot being red or a certain "hot color" and cold being purple or a "cold color"), then the scammer would place down a Mithril seed and see what color comes up. Usually, the scammer always wins, and gets to keep the money. But if the scammer doesn't win, they wouldn't usually have the money to pay the victim, and would log out. This can be reported by using the item scamming button under Honour. Some people who do Hot/Cold aren't usually scammers, and people don't usually fall for them even if they aren't scammers, so this scam is usually rare.
An unknown player named DJ Arab figured out how to win 90% of the time as the victim but hasnt released the strategy as of now.
Example[]
Scammer: "Hot/Cold x2 up to <number>"
Victim trades scammer and offers usually a high amount of money.
Victim then specifies either hot or cold.
Scammer puts down a Mithril Seed. The flower doesn't match.
Scammer wins the money.
Technically, the victim is not scammed, making the scammer free to go.
Alternate way[]
Scammer: "Hot/Cold x2 up to <number>"
Victim trades scammer and offers a high amount of money.
Victim chooses hot or cold.
Scammer plants a Mithril Seed. The flower matches.
The scammer, usually that doesn't have enough money to pay, logs out.
The victim is scammed, and may now report the scammer for scamming under Honour.