Okay. General rules.

Don't Heal.

Gesture before you attack

Allow opponent to apply whatever buffs (disputed)

Shake shield before attacking (Raise shield repeatedly)

Don't Heal

Here's how not to be a dick invading.

You can break these rules if

a) Host heals

b) 2 or more players attack you at once

c) Host is hiding like a bitch

d) You feel like it (it's a game)

1) Don't attack while I'm fighting PVE

2) Don't run into PVE's to heal aka get host attacked

3) Try to wait until I'm alone

4) If I have summons fight them first

If I summon you.

1) Usually pretty obvious if fight club, People waiting on edge.

2) If host points follow their direction

3) Wait until fight is over before joining in (unless more than 1v1) Than it's a free for all

4) You can heal after killing an opponent (unless obvious 2v2)

Arena (All rules above)

If any of the rules above are broken, feel free to break all the rules.

Disrespect (bad)

Spamming throwables

Cheap magic spells

Gesturing after unfair fight (killing while fighting PVE)

Disrespect (good)

Single throwable to kill someone (don't miss or you're an ass)

Thron Armor

Parrying then armor changing.

Honestly overall it really just depending on what you think.

Don't heal unless they do

And don't be a douche bag

besides that have fun, and if it pisses you off don't do it.