Anchor

The ability to anchor is mentioned in GURPS Powers as an inherent trait of Insubstantiality, including both floors and vehicles.
This differs from 3e where only floors were free, to Hitch a ride was a power which some spirits lacked via the Missing Power limitation called Can't ride in vehicles
4e hasn't yet explained the mechanics of anchoring, such as how often you can switch what you are anchored to, whether or not other insubstantial enemies can break your anchor, whether you revert to another anchor if your anchor is broken, etc.
For example:
*if an insubstantial anchors to a car, are they still anchored if another insubstantial knocks them off?
*if an insubstantial anchors to a ladder hanging from a helicopter, what happens if their hand is cut off?
*if an insubstantial anchors to a horse's saddle, can the horse use Break Free or Bucking Bronco to get them off?
==Knockback approach==
Perhaps it can be possible for spirits to consent to suffer knockback from normal attacks as an "in-between" state.
This could explain how for example they could ride in a car (allowing car to "shove" them) without actually suffering a car crash.
Basically if we look at Insubstantiality treating attacks as "No Wounding" / "No Blunt Trauma" / "No Knockback" and they can switch between "all 3" and "none" then allowing to only apply that PARTIALLY as a fine level of control could explain allowing the world to move them.
You could also let them specify how many points of HP they apply them to (since you can shift ALL of them between 'affectable' and 'unaffectable' states)
"why I can stand on the ground and not have gravity pull me through it" would be explained by that: you are constantly "falling" and "colliding" with the ground: you fall with the force of 10HP creating BIG DAMAGE (and BIG KNOCKBACK) but no INJURY: this "bounces" you into the air at a rate of 1 yard per damage (you reduce HP affected to 1 at this point) and this is what keeps you "above the earth".
This would also explain how insubstantials can walk on air: they "collide with air molecules" at 1 HP or less, minimizing HP affected by knockback until it's enough to launch them up
==Telekinesis approach==
One could treat the "two TK hands" as 1 grappling the spirit and 1 grappling the thing it wants to stay affixed to
This would avoid needing direct contact between a spirit or thing in situations where they did not want a direct ability to grapple them or vice versa.
The concerns of "grappling is mutual" are mitigated by such a degree of separation
==See also==
*Anchored for Warp
*Clinging for stickiness in general
**Gecko Grip perk in powers
*Dependency
*Immovable Stance
*Ship’s anchor
*Spirits of Place
*TK Tether to aid the grappling with a single object of note (or perhaps a single person) and maybe pulling lighter bodies to objects instead of light objects to bodies
Category:Rules