Spell Pen question

[Foxmoon]

At what level does Spell Penetration start to become necessary for an offensive caster cleric?

[Rusty_Can]

It depends:
- on the spells you are planning to cast: e.g. Greater Command, Destruction, Symbols, Implosion require Spell Resistance checks; Blade Barrier, Harm, Cometfall don't;
- your targets.

Generally, Spell Penetration starts becoming an issue in Vale of Twilight.