diff --git a/polymer/eduke32/source/actors.h b/polymer/eduke32/source/actors.h
index 3bbaa6d2b..cd1722701 100644
--- a/polymer/eduke32/source/actors.h
+++ b/polymer/eduke32/source/actors.h
@@ -263,6 +263,7 @@ enum sflags_t {
     SFLAG_ROTFIXED         = 0x00020000,
     SFLAG_HARDCODED_BADGUY = 0x00040000,
     SFLAG_DIDNOSE7WATER    = 0x00080000, // used temporarily
+    SFLAG_NODAMAGEPUSH     = 0x00100000,
 };
 
 // Custom projectiles "workslike" flags.
diff --git a/polymer/eduke32/source/game.c b/polymer/eduke32/source/game.c
index c34e569cb..7735c050a 100644
--- a/polymer/eduke32/source/game.c
+++ b/polymer/eduke32/source/game.c
@@ -10691,6 +10691,7 @@ static void G_LoadExtraPalettes(void)
 }
 
 #define SETBGFLAG(Tilenum) g_tile[Tilenum].flags |= SFLAG_HARDCODED_BADGUY
+#define SETNDPFLAG(Tilenum) g_tile[Tilenum].flags |= SFLAG_NODAMAGEPUSH
 
 // Has to be after setting the dynamic names (e.g. SHARK).
 static void A_InitEnemyFlags(void)
@@ -10729,8 +10730,17 @@ static void A_InitEnemyFlags(void)
     SETBGFLAG(BOSS4);
     SETBGFLAG(RAT);
     SETBGFLAG(ROTATEGUN);
+
+    SETNDPFLAG(TANK);
+    SETNDPFLAG(BOSS1);
+    SETNDPFLAG(BOSS4);
+    SETNDPFLAG(BOSS2);
+    SETNDPFLAG(BOSS3);
+    SETNDPFLAG(RECON);
+    SETNDPFLAG(ROTATEGUN);
 }
 #undef SETBGFLAG
+#undef SETNDPFLAG
 
 extern int32_t startwin_run(void);
 static void G_SetupGameButtons(void);
diff --git a/polymer/eduke32/source/gamedef.c b/polymer/eduke32/source/gamedef.c
index 46b6e368d..b1f7e2057 100644
--- a/polymer/eduke32/source/gamedef.c
+++ b/polymer/eduke32/source/gamedef.c
@@ -4570,6 +4570,7 @@ static int32_t C_ParseCommand(int32_t loop)
                     continue;
                 }
 
+                // XXX: may remove bits set in A_InitEnemyFlags!
                 g_tile[j].flags = *g_scriptPtr;
 
                 continue;
@@ -6170,6 +6171,7 @@ static void C_AddDefaultDefinitions(void)
     C_AddDefinition("SFLAG_NOCLIP", SFLAG_NOCLIP, LABEL_DEFINE);
     C_AddDefinition("SFLAG_SMOOTHMOVE", SFLAG_SMOOTHMOVE, LABEL_DEFINE);
     C_AddDefinition("SFLAG_NOTELEPORT", SFLAG_NOTELEPORT, LABEL_DEFINE);
+    C_AddDefinition("SFLAG_NODAMAGEPUSH", SFLAG_NODAMAGEPUSH, LABEL_DEFINE);
 
     C_AddDefinition("STR_MAPNAME",STR_MAPNAME,LABEL_DEFINE);
     C_AddDefinition("STR_MAPFILENAME",STR_MAPFILENAME,LABEL_DEFINE);
diff --git a/polymer/eduke32/source/lunatic/con_lang.lua b/polymer/eduke32/source/lunatic/con_lang.lua
index 74b65195f..d78e731d0 100644
--- a/polymer/eduke32/source/lunatic/con_lang.lua
+++ b/polymer/eduke32/source/lunatic/con_lang.lua
@@ -196,6 +196,7 @@ SFLAG = {
     SFLAG_ROTFIXED         = -0x00020000,
     SFLAG_HARDCODED_BADGUY = -0x00040000,
     SFLAG_DIDNOSE7WATER    = -0x00080000,
+    SFLAG_NODAMAGEPUSH     = 0x00100000,
     -- RESERVED for actor.FLAGS.chain_*/replace_*:
     -- 0x08000000, 0x10000000, 0x20000000, 0x40000000
 }
diff --git a/polymer/eduke32/source/lunatic/defs.ilua b/polymer/eduke32/source/lunatic/defs.ilua
index 6f29d06f6..b578bc7f8 100644
--- a/polymer/eduke32/source/lunatic/defs.ilua
+++ b/polymer/eduke32/source/lunatic/defs.ilua
@@ -2110,6 +2110,7 @@ local function our_gameactor(args)
     -- All good, set the tile bits in initial run and register the actor!
     -- XXX: Need to see if some other state living on the C side is clobbered
     -- by Lua state recreation.
+    -- TILE_FLAGS_SET_ONLY_ON_FIRST_RUN
     if (g_firstRun) then
         -- NOTE: when chaining, this allows passing different flags which are
         -- silently ORed. This may or may not be what the user intends, but it
diff --git a/polymer/eduke32/source/lunatic/doc/lunatic.txt b/polymer/eduke32/source/lunatic/doc/lunatic.txt
index d4859fa31..ee0e99797 100644
--- a/polymer/eduke32/source/lunatic/doc/lunatic.txt
+++ b/polymer/eduke32/source/lunatic/doc/lunatic.txt
@@ -1115,7 +1115,7 @@ Provides a mapping of symbolic names to values applicable as sprite
 Contains symbolic names of values applicable to <<gameactor,`gameactor`>>'s
 `flags` input argument, most of which are described there. +
 `SHADOW`, `NVG`, `NOSHADE`, `NOPAL`, `NOEVENTS`, `NOLIGHT`,
-`USEACTIVATOR`, `NOCLIP`, `SMOOTHMOVE`, `NOTELEPORT`.
+`USEACTIVATOR`, `NOCLIP`, `SMOOTHMOVE`, `NOTELEPORT`, `NODAMAGEPUSH`.
 
 //`BADGUY`,
 
diff --git a/polymer/eduke32/source/lunatic/test.lua b/polymer/eduke32/source/lunatic/test.lua
index 7124922de..ff3d80d1c 100644
--- a/polymer/eduke32/source/lunatic/test.lua
+++ b/polymer/eduke32/source/lunatic/test.lua
@@ -525,6 +525,10 @@ gameactor{ D.APLAYER, AF.chain_end,
     end
 }
 
+-- Add NODAMAGEPUSH flag to NEWBEAST.
+-- XXX: Doesn't work because of defs.lua: TILE_FLAGS_SET_ONLY_ON_FIRST_RUN
+gameactor { D.NEWBEAST, AF.chain_end + AF.NODAMAGEPUSH, function() end }
+
 -- Also test actor code chaining: strength is doubled.
 gameactor
 {
diff --git a/polymer/eduke32/source/sector.c b/polymer/eduke32/source/sector.c
index f9def7340..d8be8f250 100644
--- a/polymer/eduke32/source/sector.c
+++ b/polymer/eduke32/source/sector.c
@@ -2265,7 +2265,7 @@ void A_DamageObject(int32_t i,int32_t sn)
                         A_Shoot(i,BLOODSPLAT4);
                     }
 
-                if (PN != TANK && PN != BOSS1 && PN != BOSS4 && PN != BOSS2 && PN != BOSS3 && PN != RECON && PN != ROTATEGUN)
+                if (!A_CheckSpriteFlags(i, SFLAG_NODAMAGEPUSH))
                 {
                     if (sprite[i].extra > 0)
                     {