Add Very Long (15 Waves) and Longest (20 Waves) to the selectable Length

Check the Steam discussions. We need a more difficult KF2.

And I'm always too fast at completing 10 Waves at any difficulty. I would like to stay about 90 minutes per match.

Don't let us reward less Dosh at so many waves, because you can also spawn more enemies (at all and at once) to keep the difficulty up.

Only players with at least perk level 15 would be able to join any match with Longest (20 Waves) as Length. Server admins can disable that. If the player joins, he has 20 seconds to pick a perk or a perk with level 15 or higher will be picked automatically. During the match, the perk can be only changed to a perk with at least level 15. This is all required to not go around it. It doesn't count at Normal difficulty.

After 10 waves, a lower percentage of xp will be rewarded at Very Long (15 Waves) and Longest (20 Waves)!

Add Very Long (15 Waves) and Longest (20 Waves) to the selectable Length