Before Going to the Lab. You must get the Algae Cakes from Cueball. Do this by Speaking to Trixie and finding out whats shes doing here, then go over and speak to Edna who will want you to get Trixie fired. This conversation unlocks Cueball.
Get the Algae Cakes from him and the Postcard (for a separate missable achievement). Make sure while at the expo you offer a cake to everyone there, The Guy, Edna, Arty, Doc, Trixie, (Cueball wont eat one but offer him anyway). When they all have eaten one go to the lab
Once in the lab, pretty much exhaust the conversation options with Emmett offering him an algae cake.
This will pop:
Here is a guide for other Lab Achievements to get while Here:
Go to the back of the Lab and
Grab the Oil CanGo over to the Stack of Mind Maps. Interact with them 2- 3 times. This will pop: The EDNA WAS RIGHT ACHIEVEMENT
Now Select the Easel at the back of the labwhen Emmett asks about the picture make sure you select
Its not So Good Now go and pick up the photo album to your inventory.
Now Pick up the small Cleaning Spray bottle and check that it is in your inventory.vNow, Go to the exit and select to leave this will bring about a short cutscene (and you wont leave) Talk to Emmet and select the dialogue
You Can't Marry Edna then
Youre supposed to marry someone else. This will pop
Make Sure you do not leave the lab. Select the
MindMap Switch Test icon
Proceed with the Objectives, The lights on Emmets helmet indicate his mood. Each Slide shows a new image, the idea is to make Emmett appear happy when negative images appear and make him feel Negative when Happy Images appear. (hint: to make him negative turn the valve, to make him happy, open the stew) If you are going from Happy to Negative you must turn the valve twice and vice versa. When done correctly the Mindmap test will break so you know you have done it right. Go over to the Mental Alignment Meter and place the MindMap printout into it. Degenerate Criminal will flash popping the:
Switch the Mind Map card with Emmett's on the wall.
Make A Save Just In case: And leave the lab.
Back at the expo you must take care of some objectives:
Give the Postcard of Trixie to Edna, Go to the display and use the spray bottle on the cave man then grab the mink fur from him. Now you can give Trixie all of the items she requested so use the prism (from the future display tent), photo album(from the lab), and mink fur on her to progress
Go back to the DeLorean placing the spray bottle inside it, then go over to Doc to get him to use the car. Repeat that twice and the cleansing spray will be aged to perfection; grab it and the scene will change.
This brings you back to the lab a second time. Send Edna Away and try and use the Aged Spray on Emmett. This will start another cutscene and return you to the expo. Go through a dialogue with Doc telling him that Edna will end up Alone and Miserable, just to quicken up the cutscene. Doc will fly away in the Delorean and the beloved pop will make it all worthwhile.