Entrance Randomizer will not have any effect until you get to Hell's Kitchen. Lots of locks doors and elevators have buttons added on their backside to allow backwards travel, these will not be listed here. Also some helicopters will not fly away in order to allow you to backtrack more.

If you need help, you can click the spoiler button

Airfield (Mission 3)

03_NYC_BATTERYPARK

Added a rebreather

03_NYC_AirfieldHeliBase

Disabled the falling platforms, and also added a rebreather

03_NYC_AIRFIELD

Added a rebreather

Hong Kong (Mission 6)

Tong's Base

Tong's base is always in the vanilla location.

06_HONGKONG_WANCHAI_CANAL

There is a boat that will allow you to climb up into the pipe that is normally the exit from the UC.

06_HONGKONG_VERSALIFE

There is a datacube somewhere with the code for the elevator in Wanchai Market.

06_HONGKONG_STORAGE

There is a datacube somewhere with the code for the keypad in the garage.

Vandenberg and Oceanlab (Mission 12+14)

12_Vandenberg_Cmd

The door to the back side of the tunnels now has a key somewhere on the map, in a randomized location.

14_Oceanlab_Lab

When coming up from the UC side first, you'll need these extra keys.

extra Crew Module Access key

backtracking button for the door with the keypad

extra Greasel Labs key

List some additions that will help you beat the game, like added backtracking buttons or datacubes...

DXRBacktracking additions are always enabled even when entrance rando is disabled https://github.com/Die4Ever/deus-ex-randomizer/blob/master/DXRModules/DeusEx/Classes/DXRBacktracking.uc

DXREntranceRando ApplyFixes() is only when entrance rando is enabled https://github.com/Die4Ever/deus-ex-randomizer/blob/master/DXRModules/DeusEx/Classes/DXREntranceRando.uc#L729-L748

some stuff in DXRFixup might be worth mentioning too, like the add_datacubes list https://github.com/Die4Ever/deus-ex-randomizer/blob/master/DXRModules/DeusEx/Classes/DXRFixup.uc#L78-L84

Also some exceptions, like Tong's Base is always at the vanilla teleporter

And maybe also list some vanilla things that are not well-known but helpful for entrance rando