MTG Salvation

I don't have a full decklist, and if I should before posting here then I'm sorry and I'll gladly make any changes. I'm looking for suggestions, as I seem to be the only person who loves sitting behind enchantments and making faces at my friends. I want to make a deck using Ertai, the corrupted as a commander (to stop wipes that would hit my enchantments) that would keep itself from being focused using effects like ghostly prison, propaganda, norn's annex, and no mercy. Creatures would be either things with protection from creatures or damage so that they could block forever or creatures with effects that either benefit everyone (to discourage attackers) or make it difficult to be attacked. Things like Teysa, Envoy of Ghosts or Darien, King of Kjeldor.

Do you guys have any hidden gems you favor along the lines of propaganda (also, are they just called propaganda effects or???) or bombs that I can slap on an evasive creature later in the game when my opponents have killed each other off? My friends tend to use a lot of creatures, be scared of combat math, and get kicked out if they go infinite very often.

This cards all do what you are trying to do in different ways:

Collective Restraint
Energy Field with Rest in Peace
Protective Sphere
Sphere of Safety

You can see more examples from the link in my signature. Dechs Kaison also has a nice list here.

I wouldn't call any of these hidden gems...

• Blinding Angel
  
• Dread
  
• Lightmine Field
  
• Moat
  
• Teferi's Moat
  
• Aurification
  
• Magus of the Moat
  
• Peacekeeper
  
• Stormtide Leviathan
  
• Wall of Nets
  
• War Tax
  
• Windstorm Muse

Koskun Falls

With all the cards that say creatures can't attack you, how about some stuff to force creatures to attack? Courtly Provocateur and Angel's Trumpet come to mind. That way you're saying "creatures must attack.... someone else."

Glacial Chasm and Mourner's Shield for options outside of enchantments or creatures.