Another Stealth/Giganticus Lupicus Post :(
As a thief you have a million different ways to avoid Lupi’s attacks, so I guess you’ll just have to rely on something else. Even without it we’re in a far, far better place than most classes for that fight. Lupi is so much more relaxing on my thief than on my necro, or even my warrior.
Channeled attacks were actually never affected by stealth (assuming the channel started before you stealthed). In the future, 15 in acro + withdraw and vigor on heal will keep you alive better during the second phase. If that messes with your build too much, you can save your initiative for SB 3 spam during his AoE spam and save your dodges for his underground attack. I tend to save SR for when teamates go down and throw it on them while letting our guardian res them while I try to hold pressure on myself.
Just disregard stealth entirely. Lupi is actually really easy for a thief, primarily because all his attacks are extremely telegraphed and even 10 points in acrobatics with withdraw allows for enough endurance to dodge everything (go 5 more for feline grace and mainhand dagger for the overkill). The only thing that is even remotely a threat is dome of doom. If that is a concern just sacrifice dps and go with a sword.