2-3 paragraphs are minimum for most games, but do understand a lot of people write collaborations which make posts look huge and oftentimes, reacting to relevant posts just can't be done in a couple paragraphs. It might look intimidating, but keep in mind that you don't have to finish a post in a si gle sitting. It's not uncommon for games to go a couple days, if not a week or more, without an IC post and still be perfectly healthy. It's a classic case of quality verses quantity, even if sometimes people write massive walls of unnecessary text. Don't fret about it!