diff --git a/rogueviz/ru/classes.cpp b/rogueviz/ru/classes.cpp
index d663ca62..0606d2c4 100644
--- a/rogueviz/ru/classes.cpp
+++ b/rogueviz/ru/classes.cpp
@@ -114,6 +114,7 @@ struct room {
   int timed_orb_end;
 
   vector<unique_ptr<struct entity>> entities;
+  vector<unique_ptr<struct room_mod>> room_mods;
 
   eWall at(int x, int y) {
     return eWall(block_at[y][x] >> 3);
@@ -580,6 +581,17 @@ struct fakesaw : public saw {
   void act() override;
   };
 
+struct room_mod {
+  virtual void draw() {}
+  virtual void act() {}
+  };
+
+struct reflector : public room_mod {
+  xy pos1, pos2;
+  void draw() override;
+  void act() override;
+  };
+
 /* entities with a defined 'respawn' location */
 struct located_entity : public entity {
   xy respawn;
diff --git a/rogueviz/ru/entity.cpp b/rogueviz/ru/entity.cpp
index b890bee1..508f1e30 100644
--- a/rogueviz/ru/entity.cpp
+++ b/rogueviz/ru/entity.cpp
@@ -1105,5 +1105,37 @@ void rollingsaw::act() {
     }
   }
 
+void reflector::draw() {
+  hyperpoint h1 = to_hyper(pos1);
+  hyperpoint h2 = to_hyper(pos2);
+  for(int i=0; i<=100; i++) {
+    hyperpoint h = lerp(h1, h2, i/100.);
+    auto p = from_hyper(h);
+    curvepoint(eupush(p.x, p.y) * C0);
+    }
+  queuecurve(scrm, 0xFF0000FF, 0, PPR::LINE);
+  }
+
+void reflector::act() {
+  auto x1 = to_hyper(pos1);
+  auto x2 = to_hyper(pos2);
+  transmatrix T = gpushxto0(x1);
+  x2 = T * x2;
+  transmatrix T1 = spintox(x2);
+  T = T1 * T;
+  x2 = T1 * x2;
+  for(auto& e: current_room->entities) if(e->existing && e->get_name() != "REFLECTOR") {
+    hyperpoint h_at = T * to_hyper(e->where);
+    hyperpoint h_was = T * to_hyper(e->where - e->vel);
+    if(h_at[0] >= 0 && h_at[0] < x2[0])
+    if(h_was[0] >= 0 && h_was[0] < x2[0])
+    if(h_was[1] > 0 && h_at[1] <= 0) {
+      h_was[1] *= -1;
+      h_at[1] *= -1;
+      e->where = from_hyper(iso_inverse(T) * h_at);
+      e->vel = e->where - from_hyper(iso_inverse(T) * h_was);
+      }
+    }
+  }
 
 }
diff --git a/rogueviz/ru/load-world.cpp b/rogueviz/ru/load-world.cpp
index 4d5288d7..f6104005 100644
--- a/rogueviz/ru/load-world.cpp
+++ b/rogueviz/ru/load-world.cpp
@@ -465,6 +465,12 @@ void load_room(fhstream& f, cell *c) {
           ev.back().wall = eWall(i), ok = true;
         if(!ok) println(hlog, "warning: SWITCHEVENT wall not recognized");
         }
+      else if(cap == "KREF") {
+        auto b = std::make_unique<reflector>();
+        b->pos1 = get_xy();
+        b->pos2 = get_xy();
+        r.room_mods.emplace_back(std::move(b));
+        }
       else println(hlog, "unknown mapline ", s);
       }
     else println(hlog, "unknown mapline ", s);
diff --git a/rogueviz/ru/render.cpp b/rogueviz/ru/render.cpp
index 7db50fad..2d57b091 100644
--- a/rogueviz/ru/render.cpp
+++ b/rogueviz/ru/render.cpp
@@ -349,6 +349,7 @@ void man::draw() {
 void render_room_objects(room *r) {
   initquickqueue();
   if(r == current_room && m.visible_inv() && m.existing) m.draw();
+  for(auto& e: r->room_mods) e->draw();
   for(auto& e: r->entities)
     if(e->existing && (cmode == mode::editmap || (e->visible(r) && e->visible_inv()))) {
       if(e->hidden() && !m.can_see(*e)) continue;
diff --git a/rogueviz/ru/ru.cpp b/rogueviz/ru/ru.cpp
index 2f2f9458..a7d013f4 100644
--- a/rogueviz/ru/ru.cpp
+++ b/rogueviz/ru/ru.cpp
@@ -150,6 +150,8 @@ vector<unique_ptr<struct entity>> new_entities;
 void playing_frame() {
   auto& ents = current_room->entities;
 
+  for(auto& e: current_room->room_mods) e->act();
+
   for(auto& e: ents) if(e->existing) e->preact();
 
   m.act();