Bard/tamer is fine. I find shimmering easiest to do with tamers. But use a discord bard. Spellweaving tamer with a level 6 focus is very good as well.
Leave pet in the corridor with the ankh, then go into the room discord the boss. It normally takes several attempts, coz the barding difficulty is 160. Also discorded peerless only lose 5% as opposed to 28% for legendary discorders. But every little bit helps stack things in my favor.
Once discorded, bring pet in, tell it to follow the peerless (optional, I just hate it when the pet lose track of it's target and come running back with me, luring the peerless towards me), then all kill.
To heal, just stand as far as possible (I keep 8 tiles away, more time to react if the mobs decide to switch targets) and use In Vas Mani to heal. Need meditation and MR equipment to keep up with mana expenditure though.
Discord minions when they appear and set your pet against them first. These lose 28% stats when discorded and are easy kills. But if you let the peerless spawn too many minions, they can tear your pet apart.
If you are careful to recast Gift of Life, you can swap vet out and get spellweaving in its place. The danger is if you get hit by a lag spike and pet dies without gift of life active.
Impt things to remember:
1) if your pet dies and you can't rez it, you'd most likely have to leave
2) if you use login/logout to try to save pet, and if pet dies before it gets autostabled, the GoL rez gump will not appear (it actually appears, but you are logged out)
Tip - always cast GoL on yourself, then on pet. When yours time out, you will know that the pet's GoL has timed out as well. Then recast on both. Cast Gift of renewal to give yourself a bit of breathing room if needed.
WoD the peerless when it gets reduced to 35% hp. This really speeds up the process a lot.
Oh, use either a Cu or GD. Rune beetles are a bit difficult to keep alive.