Blightzerker - Video Guide

few comments and a small suggestion for improving the tree :)
you can do no regen maps as a berserker because of of warcry mana recovery. it might be a pain in the ass for boss damage (and still a bit in general), but it should be doable if absolutely necessary. it's just like hexproof maps. can be done, but not advisable.
clarity is not really needed for the same reason.
vaal skills can't be cast by trigger skills, so no reason to watch the CWDT/vaalhaste level.
+1 for the aquamarine flast of heat. this combination is fricking awesome. especially in tul breaches, holy crap this shit is op there.
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if you really want to go and grab the witch starting spelldamage nodes, come from the left side and don't go through practical application. if you need the dex though, you could always take the 30 dex node, as the "left" way is 1 point less.
alternatively you could leave these out completely, they are 74% spell damage for 8 skill points (9 for your current route), and take the Templar starting area spell damage nodes. instead, which are 66% for 5 points. then put the remaining 3 points (or 4 points in your current route) into the light of divinity wheel near the amplify cluster, which is another 35% spell damage, so it is 101% spell damage for the same amount of skillpoints.