If you have read, and i'm sure you did, the Parasite Suit is said to lowering your rank to A Wich is not true. The use of the armor it self doesn't lower your ranking. You can also use the Armor mod, and the Mist mod, without triggering the Rank lowering status only the Camo does it.
I have 2 Questions: Do we allow it in Any% S rank ? Do we allow it in Peacenik runs ? I feel like the answer should be the same in both category.
Before Answering keep it mind 3 things: Enemy doesn't see past 10 meters with the mist up. Wich is just huge making you more or less invinsible. The Armor is basicly a cheat mod you'r barely invincible. It change a lot of thing for Peacenik, it change a little for Any% S Rank.
Hope you guys will give your input for this.
I'd say to ban it at least from peacenik. Any% S is already easy enough to not need it, so that wouldn't hurt, either. I don't have an opinion for full game runs (you get it so late anyway so it's only ever going to be useful for all 51 missions and 100%.)
The mist makes things way too easy and monotonous, basically just sprint through everything without a worry. This obviously doesn't look entertaining, nor is it challenging at all.
Armor is okay IMO. It's only ever useful in few select missions where stealth is not the preferred method anyway, so it's not going to make a huge dent in times or entertainment. Sure, you get to survive Quiet's shots in the extreme version, but with enough skill, she won't be shooting you anyway. Same deal with Sahelanthrophus; Battle dress offers enough protection for the one minute it takes to kill it. People run past the sniper skulls, so it's not useful there, either. The only mission I can see it making a dent is the Metallic Archaea, both versions. Then again, who cares about that since stealth or gtfo as entertainment value goes.
tl;dr: Ban mist. Armor okay until someone figures out a game breaking exploit with it. At least limit mist to one use of the lower grade if it must be allowed for any% S. Otherwise it'll destroy the entire speedrun structure.
