Maximum of 1 of each in a deck:
• Multi-colored enhancement, Hero, or Evil Character
• Dominant (lamb icon or grim reaper icon card)
Maximum of 1 of each per 50 cards in a deck:
• Card that has a special ability (text over the picture). Example: A fifty-six (56) card deck may contain only one Authority of Christ, one Repentance, etc. A one-hundred (100) card deck may contain no more than two Authority of Christ, two Repentance cards, etc. A one-hundred fifty (150) card deck may contain no more than three of any individual special ability card.
Maximum of 3 of each in a deck:
• Single-colored Heroes, Evil Characters and enhancements that do not have a special ability.
Other rules:
• The number of sites may not exceed the number of Lost Souls in a deck.
Based on this, I've always played where you can have as many no SA single color sites as you want, provided your total number of sites is equal to or less than your number of lost souls.