diff --git a/assets/prelude.ld b/assets/prelude.ld
index 8669db9..03ce4ae 100644
--- a/assets/prelude.ld
+++ b/assets/prelude.ld
@@ -1299,7 +1299,11 @@ let pd! = pendown!
 
 fn pencolor! {
 	"Changes the turtle's pen color. Takes a single grayscale value, an rgb tuple, or an rgba tuple. Alias: `pencolour!`, `pc!`"
-	(color as :keyword) -> add_command! (:turtle_0, (:pencolor, color))
+	(color as :keyword) -> {
+		if color (colors)
+			then add_command! (:turtle_0, (:pencolor, color))
+			else panic! ("There is no color named {color} in the colors dict.")
+	}
 	(gray as :number) -> add_command! (:turtle_0, (:pencolor, (gray, gray, gray, 255)))
 	((r as :number, g as :number, b as :number)) -> add_command! (:turtle_0, (:pencolor, (r, g, b, 255)))
 	((r as :number, g as :number, b as :number, a as :number)) -> add_command! (:turtle_0, (:pencolor, (r, g, b, a)))
@@ -1368,16 +1372,29 @@ fn loadstate! {
 fn turtle_listener () -> {
 	receive {
 		(:forward!, steps as :number) -> add_command! (self (), (:forward, steps))
+		(:fd!, steps as :number) -> add_command! (self (), (:forward, steps))
 		(:back!, steps as :number) -> add_command! (self (), (:back, steps))
+		(:bk!, steps as :number) -> add_command! (self (), (:back, steps))
 		(:left!, turns as :number) -> add_command! (self (), (:left, turns))
+		(:lt!, turns as :number) -> add_command! (self (), (:left, turns))
 		(:right!, turns as :number) -> add_command! (self (), (:right, turns))
+		(:rt!, turns as :number) -> add_command! (self (), (:right, turns))
 		(:penup!) -> add_command! (self (), (:penup))
+		(:pu!) -> add_command! (self (), (:penup))
 		(:pendown!) -> add_command! (self (), (:pendown))
-		(:pencolor!, color as :keyword) -> add_command! (self (), (:pencolor, color))
+		(:pd!) -> add_command! (self (), (:pendown))
+		(:pencolor!, color as :keyword) -> if color (colors)
+			then add_command! (self (), (:pencolor, color))
+			else panic! ("There is no color {color} in the colors dict.")
 		(:pencolor!, gray as :number) -> add_command! (self (), (:pencolor, (gray, gray, gray, 255)))
 		(:pencolor!, (r as :number, g as :number, b as :number)) -> add_command! (self (), (:pencolor, (r, g, b, 255)))
 		(:pencolor!, (r as :number, g as :number, b as :number, a as :number)) -> add_command! (self (), (:pencolor, (r, g, b, a)))
+		(:pc!, color as :keyword) -> add_command! (self (), (:pencolor, color))
+		(:pc!, gray as :number) -> add_command! (self (), (:pencolor, (gray, gray, gray, 255)))
+		(:pc!, (r as :number, g as :number, b as :number)) -> add_command! (self (), (:pencolor, (r, g, b, 255)))
+		(:pc!, (r as :number, g as :number, b as :number, a as :number)) -> add_command! (self (), (:pencolor, (r, g, b, a)))
 		(:penwidth!, width as :number) -> add_command! (self (), (:penwidth, width))
+		(:pw!, width as :number) -> add_command! (self (), (:penwidth, width))
 		(:home!) -> add_command! (self (), (:home))
 		(:goto!, x as :number, y as :number) -> add_command! (self (), (:goto, (x, y)))
 		(:goto!, (x as :number, y as :number)) -> add_command! (self (), (:goto, (x, y)))