There is almost virtually no site lockout. Removing souls from the table and intentional soul drought are more common. Most players won’t use up the card slots to put in more than 2-3 sites in a deck. There’s also the Ends of the Earth multi colored site from Revelation of John that is used to access all sites. And many players include cards that generate lost souls for their opponent, as a means to rescue if there are none available (by site lock or drought) using Majestic Heavens, the various characters that capture themselves to opposite’s land of bondage from Fall of Man and Lineage of Christ sets. To summarize, avoid inserting multiple sites in attempt to site lock. But for reference, teal and clay are probably the two least good brigades used. Silver isn’t hugely popular either. Hope this helps!