User blog comment:Legionwrex/Did the Leviathan DLC really add a new twist to the endings?/@comment-1978336-20120901160023

The Leviathans are not going to invade. They don't seem to desire any sort of influence over what occurs in the galaxy, instead focusing on matters that concern themselves and themselves alone. They appear largely apathetic towards what happens in the galaxy around them as long it doesn't affect them directly. It is unlikely that the Leviathans will ever attempt to involve other forms of sapient life in their agenda, as it seems that the leviathans have gone to great lengths to prevent other species from becoming involved with them.

Once the threat posed to them by the reapers has been dealt with, the leviathans will once again withdraw themselves from galactic events. The aftermath of the Reaper War will not involved them or be influenced by them. The purpose of the leviathans in the story appears to have been to further elaborate upon the origin and purpose of the reapers.