Professional guides are a must
Skiing far away from the prepared slopes means being further away from rescue services or possibly exposed to a higher avalanche risk. Good equipment is worth its weight in gold here, but should not lead you to lull yourself into a sufficient sense of security. If you don't know the freeride areas around Engelberg (and other places in the world) like the back of your hand, you should definitely have a trained mountain guide or ski instructor with you. They can assess distances, topographical conditions and the consequences of weather changes much better than someone who only knows the terrain from Google Maps. The basic rule for all freeriders is: never go off-piste alone!