diff --git a/landgen.cpp b/landgen.cpp
index 7ce2fe78..19f9d80f 100644
--- a/landgen.cpp
+++ b/landgen.cpp
@@ -2657,7 +2657,7 @@ EX void giantLandSwitch(cell *c, int d, cell *from) {
         
       if(d == 7) {
         if(c->wall == waNone) {
-          if(hrand_monster(2000) < 20 + (items[itFrog] + yendor::hardness()))
+          if(hrand_monster(2000) < ((cwt.at->land == laFrog || items[itFrog]) ? 20 : 0) + (items[itFrog] + yendor::hardness()))
             c->monst = pick(moFrog, moPhaser, moVaulter);
           }
         }