There's a notorious bug involving Isabela and Sebastian's friendship bonuses making the rounds. The problem with Isabella and Sebastian occurs when you enter an area where they are removed from the party without going through the party selection screen. For example, entering Hawke's home will automatically remove all members of your party. Their friendship bonuses are also removed from your character since they are no longer in your party, however, this reduction is a permanent, stacking subtraction from your base value every time they are automatically removed from your party.
If you visit your home often enough with them in your party, you will experience a noticeable permanent attack speed reduction (Isabela), as illustrated in this user video:
There's a similar problem caused by Sebastian's friendship bonus, progressively reducing your overall damage resistance.
Bioware has been alerted of the issue, but while they are figuring out the source of the problem, you are advised to develop Isabela's and Sebastian's rivalry paths, simply not use them in your party, or
PC Interim Solution
If you are a PC player, you can reset your character values manually by editing the saved game. In order to manually edit the saved game file (make a backup before you edit, just in case!), you'll need to download the latest version of pyGFF, and launch the program daosavegame.exe included in that download. Open up the corresponding Dragon Age Save file (*.das) that you want to edit from your My Documents\Bioware\Dragon Age 2\Characters.
Naitaka describes the manual fix like so:
Whenever you see a friendship bonus on your abilities screen that shouldn't be there. Go to a party selection horn. Put both Isabela and Sebastian in your party, [deactivate any abilities and remove any equipment that change your attack speed and/or damage reduction], and Quick Save.
Then use the Save Editor to open up that quick save, and modify your attack speed and damage modifiers to their proper values. (5.0 for both if you don't have any other abilities or aren't wearing any equipment that changes those values.) Load your Quick Save, then remove Isabela and Sebastian from your party.
Check your Abilities screen again and see if those two abilities have been properly removed. Then check your resistance to see if your damage reduction has been reset to the right value.
This will fix the bug until the next time you either:
- Go to Hawke's Mansion without removing Isabela/Sebastian from your party first.
- Play a quest that force remove them from your party, for example, going to the Qunari compound with Isabela, or on Isabela's Companion quest in Act 2.
Thanks to windezz for compiling a list of bugs and fixes that also involve using the save editor:
- Attack Speed bug and fix:
Using the Dragon Age Save game editor (daosavegame.exe) Look for the Fire Damage Reistance value. It has an ID of 42. Seems Bioware changed the id values for stats and 42 is now Attack speed. Youll notice that under modifier it has a negative value. Simply change that to 0 and save. And presto, Hawke has normal attack speed again. If you have Isabela with her passive friendship buff to attack speed active in your party in the current save, set the modifier value to 5 instead.
- Stamina loss bug and fix:
For those who had a stable decline of Stamina (it lowered continuously throughout the game from 160 to 110), just modify the "Modifier" value of the "Defense" tab back to 0.0.
- Defense and Dexterity bug and fix: (Last Descent set bonus may cause this)
There is a inconsistency that is decreasing Defense by exactly 20. Best way to see if its affecting you is to remove all armor and equipment and deactivate any buffs affecting defense. Then in save game editor, look at the modifier - it should be 25 for rogues, 0 for warriors, and 50 for mages - without any equipment on. So, to fix it, simply increase the current modifier value by whatever is needed to get it to 25 for rogues, 0 for warriors, and 50 for mages. Also be sure to increase the "current" value by the same amount as well.
There is also a Dexterity leak, possibly caused by the Last Descent armor set bonus, lowering Dexterity by 1. Very easy to fix, same procedure there. Remove all armor and make sure the modifiers are correct. For instance rogues should have a modifier of +3 on dexterity, +2 Cunning, +1 Willpower. Also note that ID 4, which is called Magic in editor is actually Cunning, And ID 5 which is Cunning in editor is actually Willpower.
The stat with ID 10 tagged as defence in editor is actually Stamina. And that it gets stuck at -20 matches the set bonus which adds +1 dexterity and +20 stamina. Must be a problem with how the script scrubs the stats when the ability is not supposed to be active anymore.
- Injury Immunity "buff":
At a certain point (after dying a lot probably), your remaining health - the value that determines how injured you are - gets so far into the negative that you are no longer injured at all upon death + revive.
Console Interim Solution
Thanks to S0ulS7orM for posting the solution and Rubicon17 for summarizing the posts for console users:
If any of you load a game where [Isabela and Sebastian] are NOT in your party, in the Hawke section of your abilities you'll find that their friendship abilities
are still active, however they do not actually increase your attack speed/damage resistance. But when you then next rearrange your party these abilities WILL be removed reducing attack speed/damage resistance.
Also you will find that loading a save with these companions in your active party WILL apply the attack speed/damage resistance to Hawke, therefore when you remove them your stats will return to normal.
Therefore I believe the problem seems to be that when loading a save file it does not seem to correctly identify who is in the active party, instead activating all friendship/rivalry abilities regardless of active members but as Isabella and Sebastian's are the only ones that affect Hawke's stats (and therefore are the only ones visible in the Hawke section of abilities) these are the only ones that are causing a problem.
To try this theory I have made two separate save files; one with them and one without. Upon loading without them my damage resistance is -15% but upon rearranging party it reduces to -20%. Upon loading with them my damage resistance is -10% and after rearranging party it goes back to -15%. I have also tried loading without them several times and it ALWAYS decreases and using this method I have reduced my damage resistance to -75% to thoroughly test.
Solution: DO NOT SAVE UNLESS YOU HAVE ISABELA AND SEBASTIAN IN YOUR ACTIVE PARTY