Available on multiple platforms, not limited to single-player

If you don't know what to buy, you can get some of this. I've been observing this Firo for about four or five years. The total supply is 21 million.
Its characteristic is that it tends to suddenly surge and then long-term decline.
I bought it for $2 in 2020 and sold it for $10 later.
It has been declining for these years, with occasional surges, suddenly jumping from $1 to $4, and sometimes from $2 to $7. It's the kind of thing that can multiply several times within a few hours and then drop again. So I usually buy it and directly set a sell price that is double. For example, if I buy it for $2, I directly set a sell price of $4, keeping it listed for a long time and occasionally completing a transaction. Sometimes I buy back and sell again, and a single transaction can take six months to a year.
It also belongs to the category of old coins, with a low total supply, so those with patience can hold a little.