diff --git a/monster/elemental/Shadow/s_mastif.arc b/monster/elemental/Shadow/s_mastif.arc
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+++ b/monster/elemental/Shadow/s_mastif.arc
@@ -0,0 +1,47 @@
+Object s_mastif
+name shadow mastif
+face s_mastif.131
+race shadow
+anim
+facings 2
+s_mastif.131
+s_mastif.132
+s_mastif.133
+s_mastif.132
+s_mastif.171
+s_mastif.172
+s_mastif.173
+s_mastif.172
+mina
+monster 1
+sleep 1
+Wis 20
+alive 1
+hp 600
+maxhp 600
+Con 20
+speed -0.4
+exp 20000
+ac -20
+dam 13
+wc -15
+level 25
+can_see_in_dark 1
+resist_physical 50
+resist_magic 25
+resist_fire 50
+resist_cold 100
+resist_confusion 100
+resist_acid 100
+resist_drain 100
+resist_poison 100
+resist_fear 100
+resist_deplete 100
+resist_blind 100
+attacktype 32912
+weight 1000
+editable 1
+run_away 5
+attack_movement 3
+color_fg black
+end
diff --git a/monster/elemental/Shadow/s_mastif.base.131.png b/monster/elemental/Shadow/s_mastif.base.131.png
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