Heimtückischer Hehler

Activated abilities contain a colon. They're generally written "[Cost]: [Effect]." Some keywords are activated abilities and will have colons in their reminder text.

If an ability that Scheming Fence gains refers to the permanent it is on by name, the ability Scheming Fence has refers to Scheming Fence instead.

Scheming Fence gains only activated abilities. It doesn't gain keyword abilities (unless those keyword abilities are activated), triggered abilities, or static abilities.

Some activated abilities won't do anything when activated by Scheming Fence. For example, if the chosen permanent is an Equipment with an equip ability, activating that equip ability will not cause Scheming Fence to become attached because it isn't one of the subtypes which can be attached to permanents (Aura, Equipment, and Fortification).