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If the defense is low, you won't increase it by 30%! It's not +30 defense, but +30%. Let's say you have an attack of 11 and a defense of 2 for a hero at level 21 (from the manual); then, the change in defense, though not significant, will only be noticeable to Nightmares, Lords, and Arch-...
Also, regarding Light, if it comes into play (2%):
Mass Stone Skin (+12 defense) (and even at level 1 in Light, it's a desirable boon and a tasty speed boost) can significantly extend life. Unless you're taking defense for "Resilience" and "Stone Strength" +9 (defense)?
In general, for me, there are two main tactics: Gate (logistics, leadership, luck – all specific Gate boosters, Darkness) or First Strike (attack-tactics, leadership-speed aura, luck, logistics). If I'm going for Gate, I try to gather everything for it; otherwise, I go for the second...
Also, regarding Light, if it comes into play (2%):
Mass Stone Skin (+12 defense) (and even at level 1 in Light, it's a desirable boon and a tasty speed boost) can significantly extend life. Unless you're taking defense for "Resilience" and "Stone Strength" +9 (defense)?
In general, for me, there are two main tactics: Gate (logistics, leadership, luck – all specific Gate boosters, Darkness) or First Strike (attack-tactics, leadership-speed aura, luck, logistics). If I'm going for Gate, I try to gather everything for it; otherwise, I go for the second...