Game idea: pet racing

[tk3369]

I forgot where I saw a similar functionality :-) Just writing down some thoughts:

Game play

> race chicken @joe @bob 
Hey Joe, Bob:
@tk3369 is challenging you to a chicken race. Do you want to accept?
In the next 60 seconds, please choose 👍🏼  to accept, and 👎🏼  to decline.

So let's say both users accepted. The bot runs a simulation and then says:

Here's the chicken race result:
1. Bob finished in 25.87s 
2. Tom Kwong finished in 30.23s
3. Joe finished in 39.66s

This result has been recorded. Type `race rank` to see the leaderboard.

Ok, people get curious:

> race rank
Alright, the monthly pet race leaderboard is as follows:
1. Joe: 10 
2. Bob: 8 
3. Alice: 7 

The champion of the month will receive a Pet Race Champion role 🥇 🤸🏼‍♂️ 

And wants to see own history:

> race history
You past 5 races were:
1. [chicken] lost to Joe(along with Bob)
2. [pig] won against Joe
3. [pig] won against Bob, Alice
...

How does the simulation work?

Each animal has a default speed in a race, and the race track distance is standard:

Animal	Normal speed	Race track distance	Normal elapsed time
Turtle	0.05 m/s	5 m	100 s
Chicken	0.5 m/s	50 m	100 s
Pig	1 m/s	100 m	100 s

By default, everyone owns one chicken, one turtle, and one pig. Each of your pets has two characteristics:

1. Speed. This is a floating point value in the unit of m/s. See above table for the default speed.
2. Age factor. This is a percentage that handicap speed. Starting at 0%, it grows 1% every week until it reaches 10%.

Every race improves your pet's speed by 0.2%. In addition, you can train your pet for an additional 0.2% per day.

> race train chicken
Great! Your chicken's speed has improved by 0.2% and now it can run at 0.7 m/s.

> race train chicken
Sorry, you can only train your pet once a day.

Now, the actual speed of your pet in a race is calculated as:

     ActualSpeed = Speed * (1 - AgeFactor + PerformFactor)

where PerformFactor is a random number in the range of [-3%, 3%].