The Force Relay is a block added by Botania. It can be bound to other blocks, and when piston force is applied to the Force Relay, the exact same thing happens to the bound block.
To bind to another block, right-click the Force Relay with the Wand of the Forest in Bind Mode, then right-click the block to be bound to with the Wand.
To retrieve a Force Relay sneak-right click it (or use a Dispenser) with a Wand of the Forest, any other attempts to retrieve it (including Silk Touch) will destroy it.
A Force Relay can also be used to redirect a Mana pulse fired by a Mana Spreader. In order for this to work, the Spreader must have a Warp Lens applied to it and the pulse must be aimed at the Force Relay. Upon contact with the Relay, the Mana pulse will "warp" to the location of the block to which the Force Relay has been bound. Whilst "warping", the pulse appears to be redirected in a straight line towards the target block but will ignore all intervening blocks, even ones that would normally affect Mana pulses - in effect, the mana has been "teleported" to the target block. Once it reaches the target block, the "warped" Mana pulse will revert to travelling along the same direction and angle it was following before it hit the Force Relay, and will once again behave like a normal Mana pulse.
A small amount of Mana is required.
- Force Relays do not stick to Sticky Pistons, and will function as if it was a normal Piston.
- A Force Relay is not considered a valid target for Mana by a Mana Spreader. Therefore, if one wishes to use a Warp Lens to redirect Mana through a Force Relay, it must be "tricked" into firing at the Relay. This can be done manually by triggering a Redstone Mana Spreader, aiming at a Mana Prism with a Force Relay behind it, or placing a Mana Pool behind a Force Relay and aiming at the pool.