diff --git a/ka/dos.k b/ka/dos.k
index da0b667..0d9f860 100644
--- a/ka/dos.k
+++ b/ka/dos.k
@@ -12,7 +12,7 @@ start:
 
     call dir_test
 
-    ;hlt
+    hlt
 
     ; Wait for and print input indefinitely
 .1:
diff --git a/vm/dv/CPUDEV b/vm/dv/CPUDEV
index bbd83b4..5144ffe 100644
--- a/vm/dv/CPUDEV
+++ b/vm/dv/CPUDEV
@@ -46,7 +46,10 @@ IDT slots:
   513-767       maskable hardware interrupts (see ...), OVERRIDES slot 512
 
     768         a handler in this slot will receive all non-maskable hardware interrupts
-  769-1023      non-maskable hardware interrupts (see ...), OVERRIDES slot 768
+  769-1022      non-maskable hardware interrupts (see ...), OVERRIDES slot 768
+
+    1023        Uncatchable exception, guarantees shutdown. Only throwable by supervisor
+                via the CRASH instruction, or by the machine in case of irrecoverable failure
 
 A handler for some E/I must use the  'idtdone' iocall to show that it is done dealing with
 a certain E/I. If that same E/I happens again before that, the following happens:
diff --git a/vm/dv/DEVCTL b/vm/dv/DEVCTL
index 043a037..6601ac6 100644
--- a/vm/dv/DEVCTL
+++ b/vm/dv/DEVCTL
@@ -10,7 +10,7 @@ It will take registers ax0-ax7 as its parameters, and
 return a value in rdx:rax.
 
 The return value in rax is a status value:
-        ≥0          ok (>0 only if meaningful)
+        ≥0          ok (>0 only when meaningful)
         -1          unspecified error
         -2          no such device
         -3          device powered off
diff --git a/vm/in/JUMPS b/vm/in/JUMPS
index e7ad97f..cb0f43c 100644
--- a/vm/in/JUMPS
+++ b/vm/in/JUMPS
@@ -6,7 +6,7 @@
 #---------------------------------------------------------------------------#
 
 #
-# Unconditional jump (JMP) instruction
+# Absolute jump (JMP) instruction
 #
 #       RIP = $1
 #
@@ -14,7 +14,7 @@ j ri
 jmp ri
 
 #
-# RCX-dependent jump (LOOP) instruction
+# RCX-dependent absolute jump (LOOP) instruction
 #
 #       IF (RCX > 0) THEN
 #           RCX = RCX - 1
@@ -22,3 +22,22 @@ jmp ri
 #       FI  
 #
 loop ri
+
+#
+# Relative jump (BCH) instruction ("branch")
+#
+#       RIP = RIP + $1
+#
+b ri
+bch ri
+
+#
+# RCX-dependent relative jump (BOOP) instruction
+#
+#       IF (RCX > 0) THEN
+#           RCX = RCX - 1
+#           RIP = RIP + $1
+#       FI  
+#
+boop ri
+
diff --git a/vm/in/SUPER b/vm/in/SUPER
index 6e98a2f..119d90f 100644
--- a/vm/in/SUPER
+++ b/vm/in/SUPER
@@ -5,6 +5,18 @@
 # Supervisor only instructions                                              #
 #---------------------------------------------------------------------------#
 
+#
+# Crash virtual machine (CRASH)
+#
+#       THROW #1023
+#
+# Throws:
+#       #SYS if not in supervisor mode
+#       #ILL if disabled through DV
+#       #1023 otherwise
+#
+crash
+
 #
 # Initiate machine shutdown (STOP)
 #
diff --git a/vm/in/jumps.c b/vm/in/jumps.c
index 17d9617..7d672a6 100644
--- a/vm/in/jumps.c
+++ b/vm/in/jumps.c
@@ -28,3 +28,24 @@ IMPL_START_1(loop)
 }
 IMPL_END;
 
+IMPL_START_1(b)
+{
+    rip += v1;
+}
+IMPL_END;
+
+IMPL_START_1(bch)
+{
+    rip += v1;
+}
+IMPL_END;
+
+IMPL_START_1(boop)
+{
+    if (rcx > 0) {
+        rcx--;
+        rip += v1;
+    }
+}
+IMPL_END;
+
diff --git a/vm/in/super.c b/vm/in/super.c
index d5b28a2..ad3875c 100644
--- a/vm/in/super.c
+++ b/vm/in/super.c
@@ -13,6 +13,13 @@ IMPL_START_0(stop)
 }
 IMPL_END;
 
+IMPL_START_0(crash)
+{
+    CHK_SUPERV();
+    _except(ctx, 1023, "CRASH instruction");
+}
+IMPL_END;
+
 IMPL_START_0(hlt)
 {
     CHK_SUPERV();
@@ -26,7 +33,11 @@ IMPL_START_0(hlt)
                 die(0);
 
             if (evt.type == SDL_KEYDOWN)
+            {
                 console_handle_input(ctx, evt.key.keysym.sym);
+                if (evt.key.keysym.sym == SDLK_RETURN)
+                    break;
+            }
         }
     }
 }
diff --git a/vm/la/karch.lang b/vm/la/kvisc.lang
similarity index 91%
rename from vm/la/karch.lang
rename to vm/la/kvisc.lang
index 0525227..578569a 100644
--- a/vm/la/karch.lang
+++ b/vm/la/kvisc.lang
@@ -5,7 +5,7 @@
 -->
 <!DOCTYPE language SYSTEM "language.dtd">
 
-<language _name="Assembler (K-Arch)" version="1.0" _section="Sources" globs="*.k" mimetypes="text/x-asm;text/x-assembler">
+<language _name="Assembler (KVISC)" version="1.0" _section="Sources" globs="*.k" mimetypes="text/x-asm;text/x-assembler">
 
 	<escape-char>\</escape-char>
 
@@ -56,14 +56,13 @@
     	
     	<!-- KVISC -->
     	<keyword>(inv|flg|[re]?pc)</keyword>
-    	<keyword>[a-z]x[0-9]+</keyword>
-    	<keyword>[re][a-z]x</keyword>
+    	<keyword>[re][a-z][xi]l?</keyword>
+    	<keyword>[a-z]x[0-9]+[bwdlq]?</keyword>
 
     	<!-- x86-64 -->
     	<keyword>[c-gs]s</keyword>
     	<keyword>[re]?flags</keyword>
     	<keyword>([gil]d)?tr</keyword>
-    	<keyword>[re]?[ds]il?</keyword>
     	<keyword>[re]?[sbi]pl?</keyword>
     	<keyword>[x-z]mm[0-9]+</keyword>
     	<keyword>[re]?[a-d][xhl]</keyword>
diff --git a/vm/pc/except.c b/vm/pc/except.c
index 0aa178b..5eb2381 100644
--- a/vm/pc/except.c
+++ b/vm/pc/except.c
@@ -32,7 +32,7 @@ void _except(ctx_t *ctx, int _code, char *fmt, ...)
         exit(-12);
     }
 
-    if (code >= IDT_SLOTS)
+    if (code >= IDT_SLOTS || code == 1023)
         goto actually_die;
 
     //
diff --git a/vm/pc/main.c b/vm/pc/main.c
index fd1cad2..a899936 100644
--- a/vm/pc/main.c
+++ b/vm/pc/main.c
@@ -140,7 +140,6 @@ int main(int argc, char **argv)
     main_ctx.mz = MEMSIZE;
 
     main_ctx.get = bget;
-
     main_ctx.rf[RIP] = MEMOFF;
 
     if (main_ctx.mp == 0) {
diff --git a/vm/pc/sym.c b/vm/pc/sym.c
index f099f0d..68babd2 100644
--- a/vm/pc/sym.c
+++ b/vm/pc/sym.c
@@ -27,7 +27,7 @@ int create_symtab(const char *name)
             logerr("Symbol addresses in symbol table not in increasing order\n");
             logerr("Previous symbol: '%s' '%lu'\n", symtab[it-1].name, prev_addr);
             logerr("Current symbol: '%s' '%lu'\n", buf, addr);
-            exit(-55);
+            exit(-1);
         }
 
         prev_addr = addr;