Onyxia.

[Tuftears]

Because I have a grand total of three trinkets.

Mark of the Chosen: a 2% chance when you are struck to give you +25 to all stats for 1 minute. There is a quest requiring a party from the centaur heretic at the south side of Desolace. You will need to kill five Khans - there are three outside Maraudon, and two shortly into the Purple and Orange sides of maraudon respectively.

Blackhand's Breadth: +2% critical strike. A letter drops from Emperor Wyrmthalak in LBRS - not sure if it's raid-droppable. When you get it, you turn it in at Morgan's Vigil in Burning Steppes, yielding a quest to kill Drakkisath in UBRS. One UBRS raid later, you'll have a choice of three nice trinkets. Druids should take the Mark of Tyrannt for +180 armor which gets multiplied by the dire bear form.

Seal of the Dawn: +76 attack power when fighting undead, also acts as an Argent Dawn commission. Need to collect plagued flesh from Stratholme, then investigate the ziggurats. Quest starts from Light's Hope Chapel in Eastern Plaguelands.

Mark of Resolution: 1% chance to resist fear or stun, use to absorb 350-650 physical damage, effect lasts 10 secs. Quest reward from Alas, Andorhal which requires killing Araj in Western Plaguelands. Starts from Chillwind Point.

Smott's Compass: 1% dodge. Quest starts from Captain Smott in Booty Bay, on the dock near the boat.

Tal:

I think much of that has to do with the autojoin channel bug. Since the last patch there is only a handful of people in the channel at any one time. I know I've been a pest to Tuftears asking him to relay LFG adverts to the basiners but I haven't had much luck filling groups with Basiners.

Omni wrote a nice 'PermaJoin' mod to fix this.

I don't mind relaying LFG adverts to the Basin in-game guild, so do feel free to ask me if I'm on.

I think one reason there haven't been Basiners on these raids is that there hasn't been an invite posted on the Basin boards to this effect, or even requests for Onyxia-keyed or MC-attuned persons in honorables or directly.