The Excursion Funnel is a testing element originating in Portal 2. It is a beam that, depeding on a state, either pushes objects away from its emitter, or pulls objects towards it.
Taking up two tiles, this beam is exactly the size of a Portal, so it can be redirected. The beam itself affects enemies as well as the player, overriding movement as neccessary. This means that Funnels may break certain enemies whose exact position or speeds make an important difference.
Funnels can be used in place of Light Bridges when the author wants the player to move at a fixed pace, or upwards. They can also be combined with Gels to cover more surface than normal, as Gels are pushed by funnels; though Gels' relatively small lifetime may hinder that.
The emitter itself is not solid, so a mappack author can make a Funnel abruptly end by placing the entity in the air and having it reversed. Combined with very high speeds (beyond normal editor range), they can become cannons that launch the player in a given direction.
- In SE beta 9, a reversed funnel will cause the game to crash. This can easily be remedied by going into funnel.lua and, at line 220, changing
endimg = excursionfunnelendimg2to
endimg = excursionfunnelend2img
- At speed 50, the graphic stays perfectly still, though this is far beyond its normal range.