This is easy. So, very, East. So lets do it.
First: Private Groups. If they do not allow PVP, then they dont. Its THEIR group, THEIR rules; Respect those rules or get out. Permanently. That's all that ever need be said about that.
To be very clear: From this point below we are going to assume all parties involved in PVP are playing either in Open or a group that allows PVP. Now that's out of the way, lets proceed with the fix.
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First: Mechanics and Terminology:
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-Victim: The person BEING attacked
-Aggressor: The party (or wing) that fired the first shot.
-Allowed: PVP May take place without any fear of reprisal or punishment by in game mechanics
-Discouraged: Consequences exist for PVP under these circumstances.
This will become relevant below.
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When is PVP ALLOWED versus DISCOURAGED by IN GAME mechanics:
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PVP IS ALLOWED in ALL of the following circumstances. If ANY ONE of these circumstances are TRUE, PVP is Allowed without ANY further consent needed:
-Lawless/Anarchy Systems
-If Archon Delaine is the Controlling Power, and the Aggressor* is a member of Delaine's Power Play Faction, the Aggressor* suffers no penalty. This is true regardless of whether the person being attacked participates in Power Play. (Its pirate space; you knew that, and you went there anyway; deal with the consequences).
-All involved Parties are members of Power Play
-All parties are inside a Conflict Zone, fighting for opposing factions
-The party attacked has a bounty of AT LEAST (no LESS than $1000 Credits).
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If NONE of the above circumstances are true PVP is Discouraged by the following consequences:
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-The Aggressor is flagged as such, via a notice inside their cockpit.
-If the Victim wins the encounter, the Victim incurs no penalties
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-If the Aggressor wins the Encounter:
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-The Aggressor Pays the Insurance Cost for the Victim
-The Aggressor pays an "Inconveniencing Penalty" to the victim, based on their distance from the station where they respawn. The further from the station, the more they pay, up to $1 million credits.
-The Aggressor is awarded a bounty for Murder of NO LESS THAN $2 million credits. This bounty:
-Is active in ALL systems Controlled or Exploited by the faction that controls the system where the Murder took place.
-Is active in ALL systems ALLIED with the system where the murder took place
-Notice of this bounty spreads across systems at 1LY per minute, adding to the systems wherein the murderer is wanted (we do have FTL communication, remember)
-This bounty will NEVER spread to Anarchy systems
-The Aggressor CANNOT dock in ANY System wherein they have a Murder Bounty
-The Aggressor CANNOT change to or purchase another ship in ANY system wherein they have a Murder bounty
-The Aggressor's next buyback cost is increased by 25%
-The Aggressor's next ship purchase is increased in cost by 20% (additional up front insurance)
-The Aggressor has ALL reputation wiped to Zero with:
-The controller of the system where the murder took place
-That system's allies
-Any and all Navies they may have earned rep with
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SPECIAL NOTE:
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There are NO penalties assessed unless the Aggressor DESTROYS the Victim's ship. Destroying their Thrusters or FSD and leaving them stranded will net you a STEEP bounty, however, it does NOT make you a murderer. This is intended to allow for legit piracy. This means that, if the Victim SELF DESTRUCTS, the Aggressor DOES NOT face the harsh Murder penalties detailed above - only a normal bounty for attacking in the first place, in Lawful systems only.
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This probably seems overly harsh. Allow me to explain my careful reasoning here:
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This is NOT EVE Online. Destroyed ships do not drop loot. They do not reward their killers in any way. Ergo, killing "for lulz" in this universe is literally role playing as a Psychotic murderer.
Elite was built to be an immersion-oriented simulation of life in space. Dangerous, hostile space sure. But the Danger of the Elite universe was focused on the danger of LOSS. Loss of cargo to pirates. Loss of your ship by crashing during a jump, while in a RES or, yes, by Pirate encounters gone awry.
Griefers represent none of those things. Griefers are not interested in piracy. They are not interested in reasonable encounters. Piracy I support and dont mind; notice all of the above penalties are incurred ONLY in the event that the Victim's ship is DESTROYED by the Aggressor; none of the harsh Murder penalties automatically occur on ATTACK. Piracy is largely unaffected by these changes, so long as it is legit piracy with a focus on obtaining booty and not killing the target.
In a galaxy such as Elite, where killing for kicks would represent truly psychotic behavior, the psychopath would see themselves ostracized from society. Relegated to Anarchy systems and perhaps the occasional pirate backwater system with lax security. Any incursion into Lawful systems would see the Psychopath pilot constantly hounded and treated as suspicious or worse yet, completely unwanted.
It is high time the Universe of Elite began treating Psychotics as they deserve. You want to pirate? Fine; use the right loadouts; negotiate with Commanders you interdict, or leave them stranded without an FSD or Thrusters. Focus on preserving the loot as opposed to killing the Commander.
You want to be a Psycho? Fine, go live like one.
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Special Note - Unsanctioned PVP in PVE Only Private Groups
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Violating the rules of a Private Group should result in a ban from every being allowed to play in another one. The offending Account - NOT the Commander Name; the ENTIRE ACCOUNT - should be banned from EVER joining any other Private Group. It does not MATTER whether you LIKE the rules of the group. The group is NOT yours, dont play there.