This is one of the ways the game gets more difficult. Less space but the same amount of bots. Towards the end of the game, any free space would get used to spawn another bot, creating a hectic situation.

This balance of space to bot count could be managed itself by AI, potentially decreasing the amount of bots as space becomes cramped.

The other way the game could manage difficulty is the AI of the individual bots. The bots are tasked with taking space and killing you or the other bots.

In order to increase the difficulty, the bots just need to be more aggressive toward the player, attacking you whenever you leave the safety of your own territory.

If you kill an aggressive bot, the game just spawns another in it's place. The life of one individual bot doesn't matter much.

I could be over analyzing this and I don't actually have any data to back that claim up. But it's the only other major way the game could scale difficulty.

Getting to 20% or even 40% has not been too difficult. However, I think it would take a long, long time to achieve 100% due to the difficulty curve. At a minimum, you would have to be very conservative when taking territory which would end up in a very long play session.

My high score of 48% took about 10 minutes. And guess what, there is no pause button!

Strategy

So knowing what we know about the AI, we can come up with some strategies to get the most area possible.

Take the walls

The edge of the arena is the safest place since there are no enemies there. You put yourself up against a wall instead of being surrounded by the bots. You also can't die by hitting the walls (unlike Paper.io 1).

2. Wait until you know you can kill someone

The AI are bound to slip up. It's pretty easy to chill in your territory and watch a bot until they leave their space. Then, once they are a distance farther from their own territory than you are to their trail, you can strike with high certainty to kill them.

3. Take enemies space directly after killing them

When you kill a bot, their territory disappears. This is the best time to take a risk and capture the space. This is because you know other bots are not likely to be there. Just be careful of a new bot spawning in.

4. Don't venture out too far

This might be obvious, but my deaths always come from going out too far. Someone then comes into my field of view and I realize there is no way for me to make it back.

This limited field of view is what makes this game so difficult. If you could see the entire playfield at all times, then winning becomes much easier.

Metagame

The only metagame is unlocking new skins.

This is achieved by completing certain stat based challenges within the core game like getting 75% of the arena space or killing 25 players in a single round.