diff --git a/docs/destroyer.txt b/docs/destroyer.txt
new file mode 100644
index 0000000..5805b92
--- /dev/null
+++ b/docs/destroyer.txt
@@ -0,0 +1,11 @@
+Destroyer
+---------
+
+Destroyers dispose of items placed in their single slot inventory (basically
+a trash). Items can be push into destroyers with tubes from pipeworks or
+hoppers attached to the top or sides, so they are suitable for automation.
+Items cannot be pulled out of destroyers.
+
+Note that destroyers act when an item is placed in their inventory, as with
+storage indexers it is best to use the hopper from this mod to feed them
+in multi-player games.
diff --git a/docs/pistons.txt b/docs/pistons.txt
index 3ce68c7..0f67536 100644
--- a/docs/pistons.txt
+++ b/docs/pistons.txt
@@ -7,6 +7,16 @@ of the pusher when extended. Sticky piston draw back a single node in
 front of the pusher when retracted. Piston also act as a digilines
 conductor.
 
+Sticky blocks are also supported. Any sticky block structure attached to
+the pusher will also be pushed, up to the maximum setting. Any free blocks
+(not attached to the sticky blocks) in front will be pushed up to the
+maximum setting. This limit is from the pusher, not the sticky block. When
+retracting a maximum of one free block depth will be pulled.
+
+Any entities in front of or standing on a moving node are pushed/pulled,
+if nothing is in the way of their base position. Any entities against a
+sticky face are not pulled.
+
 UI
 
 Channel - digilines channel of piston.