General Boss Farming

Alright, for the most part, you can still farm all of the main bosses in hellgate, heres some info on how.

Note: PP = Party Portal and PRD = Personal Relocation Device. Also, when I refer to doing this, I mean use these skills/items, then go through the portal it creates back to town.

Shullgoth:
Boss of Covent Garden Market. Theres really no easy way to do this anymore, beyond Adrenalin Pills and running, but the runs take very little time, and he is awesome XP and loot at low levels.

In a group, just have one person run to Shulli, and then invite everyone. The invited people can then PP to the runner.

Tip: When you first enter the hellgate, there are torches on either side of the stairs, if you jump up on them, shulli will bug out and run at the wall endlessly.

314's Mind
The next major boss of the game.
Requirements: Someone who has the quest.
Step 1: Take either one person or your entire farming group into 314's mind. The person with the quest will have to enter, then everyone can PP to him. Grind your way up to The Limit of Imagination, note where your game tells you this is, its important.
Step 2: Kill 314. That simple, its a good idea to kill the last instance of him in a corner so the portal is out of the way. The person with the quest MUST NOT GO THROUGH THE PORTAL if they want look that is.
Step 3: The person with the quest drops it, this will force them to log out.
Step 4: Log back in, once your in the game re-join the party (either through the party screen or an invite). Re-get the quest, and party portal to someone who is before the limit of imagination (told you it was important). Now you just have to spawn him again by talking to Aldin.

Occulous and Abbadon
I'm making these two one section because the method is the same.

Step 1: Get to the boss's zone (Angel Passage/Tower of London).
Step 2: Kill the boss.
Step 3: One person should /leave the party
Step 4: AFTER one person /leaves, one person should drop a PRD, the rest should recall.
Step 5: The person who left should go into the nearest instance thats not connected to the boss zone.
Step 6: When the person who left finishs zoneing, they should re-join the main party, they will get kicked from their instance.
Step 7: The person who PRD'ed, should go back into their PRD when the person who left re-joins. He can check to make sure it worked (just in case) then everyone can party portal to him. Whichever boss your doing should be re-spawned.

All Essence Bosses:
Requirements: Each person needs 5 of the intended essence
You can get each member of your party a head from the essence bosses relatively easily. Just go into Wake Hallow, find the entrance, have the first person pay. The second person should PP to them, and the first person should recall. The second person can now pay, and this can continue for the entire group. When the boss dies, since everyone payed, everyone will get a head.

Easy Moloch
You can farm Moloch much like you farm Abby/Occi.
Requirements: Multiple head sets.
Step 2: Get to the Master's Court and kill Moloch.
Step 3: One person (who has a head set) should PRD back to stone henge
Step 4: Another person should drop a PRD, and the rest should recall.
Step 5: The person with the headset should pay, go into Moloch's Step, and re-join the party. They will get booted from Moloch's Step
Step 6: AS the person who left re-joins, the person who PRD'ed should walk back through. If it worked Moloch should be sitting their looking at you, everyone can PP to you, and theirs your lewt.