Omg moment: Was soloing Very Hard missions with base skills before I realized you bought skills with gold rather than some special skill points or natural progression... Doh.
If you keep them from having all 3 totems by attacking the totems, the lizard brothers won't cast boulder rain.
You only have to kill one of them and both will die.
The damage is calculated in amounts dice of various numbers of sides. ------------------------------------
1d8 means one eight-sided die, or 1-8.
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2d8 is two eight-sided die, thus 2-16 damage.
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So think Number of dice X maximum damage per dice. More dice guarantees more minimum damage, so 2d6 would be slightly superior to 1d12, because its 2-12 vs 1-12.
You can get two Zodiac Memories if you transfer from Lucid Dream and beat Zodiac Memory on Nightmare. The Infinity Space in Nightmare makes you fight all of the bosses too, so it gets tough. If you have trouble with Zodiac, just use 4 chrono matters, if you can't kill him in those 40 seconds you might want to try different builds. Also if you can do good burst damage, you might want to use 4 golden apples to chomp down his HP bar instead. If you get hit with his poison and his curse, Lifestream wont save you, because its a status effect, so if you're really worried about that look for poison immunity from stats or the Grim Reaper item.