diff --git a/classes.cpp b/classes.cpp
index db60c51a..3b83d1f1 100644
--- a/classes.cpp
+++ b/classes.cpp
@@ -600,6 +600,7 @@ static constexpr flagtype WF_TIMEOUT = Flag(18);
 static constexpr flagtype WF_CISLAND = Flag(19);
 static constexpr flagtype WF_SULPHURIC = Flag(20);
 static constexpr flagtype WF_HALFVINE = Flag(21);
+static constexpr flagtype WF_NONBLOCK = Flag(22);
 
 struct walltype {
   char  glyph;
diff --git a/content.cpp b/content.cpp
index eae65d14..54e83014 100644
--- a/content.cpp
+++ b/content.cpp
@@ -891,10 +891,10 @@ WALL( '^', 0x8D694F, "Thumper", waThumperOff, WF_WALL | WF_ACTIVABLE | WF_THUMPE
 WALL( '^', 0x804000, "Fire", waFire, WF_FIRE | WF_TIMEOUT, RESERVED, 0, sgNone,
     "This cell is on fire. Most beings and items cannot survive."
     )
-WALL( '+', 0xC0C0C0, "ancient grave", waAncientGrave, WF_WALL | WF_HIGHWALL | WF_GRAVE, RESERVED, 0, sgNone, 
+WALL( '+', 0xC0C0C0, "ancient grave", waAncientGrave, WF_WALL | WF_HIGHWALL | WF_GRAVE | WF_NONBLOCK, RESERVED, 0, sgNone, 
   "An ancient grave." 
     )
-WALL( '+', 0xD0D080, "fresh grave", waFreshGrave, WF_WALL | WF_HIGHWALL | WF_GRAVE, RESERVED, 0, sgNone,
+WALL( '+', 0xD0D080, "fresh grave", waFreshGrave, WF_WALL | WF_HIGHWALL | WF_GRAVE | WF_NONBLOCK, RESERVED, 0, sgNone,
   "A fresh grave. Necromancers like those." 
     )
 WALL( '#', 0x00FFFF, "column", waColumn, WF_WALL | WF_HIGHWALL, RESERVED, 0, sgNone,
@@ -932,7 +932,7 @@ WALL( '#', 0x8080C0, "crystal cabinet", waGlass, WF_WALL, RESERVED, 0, sgNone,
     "using an Orb of Aether, your Aether power will be completely drained."
     )
 WALL( '#', 0xC0C0C0, "wall of Camelot", waCamelot, WF_WALL | WF_HIGHWALL, RESERVED, 0, sgNone, camelothelp )
-WALL( '+', 0xA06000, "Round Table", waRoundTable, WF_WALL, RESERVED, 1, sgNone, camelothelp )
+WALL( '+', 0xA06000, "Round Table", waRoundTable, WF_WALL | WF_NONBLOCK, RESERVED, 1, sgNone, camelothelp )
 WALL( '=', 0x0000A0, "moat of Camelot", waCamelotMoat, WF_WATER, RESERVED, 0, sgWater, camelothelp)
 WALL( '+', 0x606060, "big statue of Cthulhu", waBigStatue, WF_WALL, RESERVED, 0, sgNone, 
     "These statues of Cthulhu are too large to carry, and they don't look too "
diff --git a/crossbow.cpp b/crossbow.cpp
index c3775dde..71b0447d 100644
--- a/crossbow.cpp
+++ b/crossbow.cpp
@@ -67,7 +67,8 @@ EX int loading_time() {
   }
 
 EX bool blocks(cell *c) {
-  if(isWall(c) && !among(c->wall, waMirrorWall, waMirror, waCloud)) return true;
+  if(items[itOrbAether]) return false;
+  if(isWall(c) && !among(c->wall, waMirrorWall, waMirror, waCloud) && !isNonblock(c->wall)) return true;
   // if(c->monst && isMultitile(c->monst)) return true;
   return false;
   }
@@ -97,7 +98,7 @@ EX int create_path() {
       auto cw2 = ocw2;
       if(inmirror(c)) cw2 = mirror::reflect(cw2);
       if(blocks(cw2.peek())) continue;
-
+      if(thruVine(cw2.at, cw2.peek())) continue;
 
       if(cw2.at->monst) {
         flagtype attackflags = AF_NORMAL;
diff --git a/flags.cpp b/flags.cpp
index 83506d51..72c4c028 100644
--- a/flags.cpp
+++ b/flags.cpp
@@ -37,6 +37,7 @@ WALLFLAGCHECK(isAlch, flag & WF_ALCHEMY)
 WALLFLAGCHECK(isAlchAny, flag & WF_ALCHEMY)
 WALLFLAGCHECK(realred, flag & WF_RED)
 WALLFLAGCHECK(isWall, flag & WF_WALL)
+WALLFLAGCHECK(isNonblock, flag & WF_NONBLOCK)
 WALLFLAGCHECK(isPushable, flag & WF_PUSHABLE)
 WALLFLAGCHECK(conegraphtype, flag & WF_CONE)
 WALLFLAGCHECK(isStandardTree, flag & WF_STDTREE)
diff --git a/passable.cpp b/passable.cpp
index a5f8f910..94fbb4d6 100644
--- a/passable.cpp
+++ b/passable.cpp
@@ -204,8 +204,7 @@ EX bool passable(cell *w, cell *from, flagtype flags) {
   
   if(F(P_BULLET)) {
     if(isFire(w) || w->wall == waBonfireOff || cellHalfvine(w) ||  
-      w->wall == waMagma ||
-      w->wall == waAncientGrave || w->wall == waFreshGrave || w->wall == waRoundTable)
+      w->wall == waMagma || isNonblock(w->wall))
       return true;
     }