Titanfall 2

Mission 5: Effect and Cause - Chapter 3
Difficulty: Easy

After you exit the facility, and embark with BT, flip to the past. At this point you should have collected the Scorch loadout, and two Titans will attack you, along with some other basic enemies. Using the Grenade Launcher, take out as many of the regular enemies as you can and whittle down the other Titan's health bars. If your shields run low, just flip back to the present until they recharge, as neither of the Titans that attack you have shields. Once the core is ready, simply get near the Titan with the lowest health. The Titan I killed with the core had two bars of health, and I was standing 2-3 titan lengths away from him. Simply restart from the checkpoint if your attack does not kill him. I also had to pause the game and wait a minute for every achievement in this game, so give it a second if it does not unlock right away.

A couple other things to keep in mind, you should have also collected the Brute and Tone loadouts previous to this mission, so you can restart this section and get the Fire Everything! and Angel of Death achievements as well. You should also go inside the building where you activate the bridge and unlock the Ion loadout, and if you leave one Titan with full health, or dash past the two Titans right away you can get the Face Melter achievement too.

Please let me know if I should make any changes to this, as this is my first guide.