Here are the rules:

The number starts at zero.

Each person can join either the add team or the remove team (no switching).

The adding team increase the number by one each post, the removing team decrease the number by one (you can include text or an image relating to your number). The target is 100 for the adding team and -100 for the removing team.

Finally (to prevent abuse) at least 3 people must post before the same person can post again. As the host I will not participate, but I can change these rules and correct people's numbers if they get them wrong.

~~BUT! There is a twist! If one team manages to post five times in a row, their next post counts for 10.~~

This is getting into too much of a stalemate. Therefore, I am going to change the rules slightly. Each post counts +2 and -2 from now on apart from in the following circumstances: each additional post in a row from one side after the first adds or removes an extra number. For example:

First post from adding team adds 2

Second consecutive post adds 3

Third consecutive adds 4, etc.

If the minus team were to now post, their first post would take away 2, and reset the plus team's scoring bonus. If they managed to post consecutively, they would remove 3 for the second post in a row, then 4 for the third, and so on. This change to the rules is designed to allow an ending to this game at some point. It will be interesting to see what happens, and I will be watching.

Other rules I did not mention in this update are unaffected.

EDIT: Just noticed the typo, I just corrected it.

EDIT 2: Note minor rule change regarding consecutive posts.