In addition to their basic version, Hideaway, Den, Rally Point and Hub sites also feature three variants of progressive difficulty featuring elite enemies. These variants follow an extended naming convention as follows:
Besieged Guristas Covert Research Facility is an unique cosmic anomaly found in all low sec regions that spawns two waves of Mordu's Legion cruisers and battleships equipped with webifiers and warp disruptors. Unlike other enemies, these ships are able to switch damage types to find what is most effective against a given target (they do not deal omni damage). Notable loot includes higher-end implants and ship skin BPCs, as well as special module BPCs.
In faction warfare space, faction warfare complexes show up as combat anomalies. Once someone warps to a site, it will also show up as a beacon in the overview.
Combat sites that appear as Cosmic Signatures must be scanned down using Core Scanner Probes. These combat sites can be further divided into three groups: unrated complexes, DED rated complexes, and Chemical Labs. The differences between the three are relatively minor, the most notable being that Chemical Labs require the use of Data Analyzer modules to obtain all of their rewards.
Unrated complexes have a good chance to contain a commander spawn that can drop Faction items. They may also escalate into an expedition.
The sites contain multiple deadspace rooms separated by acceleration gates. The acceleration gates separating the rooms are usually locked, in which case some condition must be fulfilled, or a key must be found to proceed. The sites also have triggers for additional defender spawns and/ or an escalation. The size of ship allowed in Unrated Complexes does not follow a predictable pattern; each site, even of the same difficulty but from a different faction, may have a different ship size limit.