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For demons, leadership is good (even though it's only 2%), so focus on developing the Gate Lord and luck. Chaos isn't very effective because the Paladin's spellcasting suffers, and the damage is low unless you take Sap Magic in-game against the League, or Fiery Wrath with fire damage. You can also take Cold Steel from Attack. That's pretty much it... Dark magic is preferable, especially Frenzy and Puppet. You can aim for Spell Power, but skills in Dark and Attack are better, for example, Tactics and Mass Spell in Dark. Definitely! Logistics, Pathfinding, and Swift Gating are essential, and consequently, Teleport Assault is very good. Light is also good, but it usually appears at level 20+. Fire Resistance is particularly good against Dungeon and Academy (especially Nazir, since he's the Lord of Fire), but you can also take defense instead, where Preparation and Hellwrath are good. And of course, machines, because the sum of Attack + Knowledge is the highest for the Paladin, which is a damage modifier for ballistas. Be sure to take Triple Ballista, and then choose either a tent or a catapult. Education is also a good choice, as it increases spellcasting and provides a direct path to: 1. Dark Revelation, i.e., a free level and our favorite morale boost, which is especially useful for demons, of which there are usually +100500 in the army :D