I love UO's ability to mix and match skills and templates. UO's lack of class restrictions, for me, the most fun MMORPG available.
The fact is there are some things that are, a bit overpowered. Some combinations of skills, items, abilities etc that are EXCESSIVELY overpowered.
Unfortunately somtimes a fix isn't as simple as flipping a switch.
For example, lets take concussion blow at its former.
to quote myself
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-Damage was calculated based on the difference in Percent of MANA and HP.
Minimum 10 damage.
Take a Character with 100 HP, 100 Mana.
This character is hit for 20 Damage
If they continue fighting and are hit with a concussion, the concussion now does 20% of its bonus damage + the concussion base 10 damage + whatever damage the weapon and spell effects hit for.
If the player instead heals themselves using 12 mana in the process and is then hit with a concussion: the concussion does 12% of its bonus damage
+ concussion base 10 damage + whatever damage the weapon and spell effects hit for.
This basically means that it is a Lose/Lose situation for the Defender and Win/Win for the attacker.
The defender essentially gets penalized no matter how they choose to fight.
This has been in the game since AOS. It did not immediately become the over used special it is now. There was the fun of uncapped armour ignores, lightning strikes, perfection slipping through in PvP, and a horde of other stuff that was much more popular.
Here is what fixing concussion touches, that I'm trying to take into consideration.
1.) PvP (the most obvious.)
2.)PvM (not as much as PvP since the damage was calculated the same against Mobs.
3.) The UO Economy: Crafters, resource gatherers, Player Vendors.
While some consider PvP changes to only affect the Fel crowd, just try to imagine the horror of crafters, vendor owners, etc if that mace they had on their vendor suddenly became as useful as the Tessen?
So rather than aiming at "nerfing" concussion blow, I instead aimed at making it more "situationally useful" with a control system to hopefully limit the rinse and repeat abuse present with alot of other things.
As for soloing bosses, I guess my un-well thought out opinion on that is: It should not be impossible, but should definitely not be remotely easy.
**Thanks JC,
I had it initially as an "Immunity" system but after explaining it to some others it was easier to explain it as kind of diminishing returns. Also some seemed to take immunity to mean that complete immunity was always achieved instead of partial immunity. Maybe I'll steal that effect saturation phrasing from you.