The Heatsinks will appear and then a custom shank will make its appearance. This is S.A.B.E.R.-2.
This massive shank makes for a unique enemy. It has a number of mounted weapons and has limited control over the room you are in. It can lower the Heatsinks, blast shields and open the middle of the floor. Throughout the fight it will summon its reinforcements. This calls in a number of Shanks and at least one Servitor. The types will vary each time. Pay attention to the announcements made throughout the fight. This will let you know if you need to worry about a large number of enemies incoming.
This Shank possesses two sets of weak points. During the first part of the battle you can inflict critical hits by hitting the forward lift devices in the front. This will eventually get destroyed. The second weak point takes some timing and precision weaponry. It will periodically open up its "head". Fire on the lighted portion of it to inflict extra damage.
When you make it to the end of the first phase of the fight, S.A.B.E.R.-2 will lower the Heatsinks. This changes the cover situation around the arena. Move to the other side and take cover behind the Blast shields that are raised.
When you clear the second phase of the fight, S.A.B.E.R.-2 will lower the blast shields. The Heatsinks will raise again and later the Blast shields.
The final phase has a tough opening. Both the blast shields and the heatsinks will be lowered and the Shock core will be exposed in the middle of the floor. SABER 2 is also extremely vulnerable at this point. The housing over its own core has been blown off. There is very minimal cover for this portion of the fight. More than anything, keep on the move. Thin out the reinforcements some and then focus on SABER 2. Inflict as much damage as you can while on the run.