I dont understand what has to do focused or wrathful crystals for survavility..
Not much but just a general tip. And you won't panic and start spamming shouts when you try to get aggro back with bad offensive crystals
To survive, you just need to dodge the correct attacks and block the correct attacks, simple. At the balder's refuge boss, you need to dodge the spinning fire attack which for lancers hits almost instantly as it starts near the front of the boss. Also step back when boss runs to the middle and starts summoning balls. If multiple balls hit you at once you're dead. Also when it targets one person, it will do 3 hit attack and last hit releases balls (actually all 3 hits release balls, but the 3rd hit may change direction if the targeted person changed position). You need to dodge that one as well. And normal boss attack, 3 hits, block the 3rd hit or you will get stunned. For blightwood boss, simply block everything and dodge the outwards moving circle attack. And move out when it summons circles on several players so you don't take heavy damage and start running around uncontrollably.