fixed sometimes referencing nil values

script/c11819616.lua

@@ -18,7 +18,7 @@ function c11819616.discon(e,tp,eg,ep,ev,re,r,rp)
 	if e:GetHandler():IsStatus(STATUS_BATTLE_DESTROYED) then return false end
 	if not re:IsHasProperty(EFFECT_FLAG_CARD_TARGET) then return false end
 	local tg=Duel.GetChainInfo(ev,CHAININFO_TARGET_CARDS)
-	return tg:IsExists(Card.IsOnField,1,nil) and Duel.IsChainNegatable(ev)
+	return tg and tg:IsExists(Card.IsOnField,1,nil) and Duel.IsChainNegatable(ev)
 end
 function c11819616.costfilter(c)
 	return c:IsFaceup() and c:IsRace(RACE_PLANT)

script/c14772491.lua

@@ -64,7 +64,7 @@ function c14772491.rcon(e)
 end
 function c14772491.thcon(e,tp,eg,ep,ev,re,r,rp)
 	local tc=e:GetLabelObject()
-	return tc:IsOnField() and e:GetHandler():IsHasCardTarget(tc)
+	return tc and tc:IsOnField() and e:GetHandler():IsHasCardTarget(tc)
 end
 function c14772491.thop(e,tp,eg,ep,ev,re,r,rp)
 	Duel.SendtoHand(e:GetLabelObject(),nil,REASON_EFFECT)

script/c31440542.lua

@@ -22,7 +22,7 @@ function c31440542.ctltg(e,tp,eg,ep,ev,re,r,rp,chk,chkc)
 end
 function c31440542.ctlop(e,tp,eg,ep,ev,re,r,rp)
 	local tc=Duel.GetFirstTarget()
-	if tc:IsRelateToEffect(e) and tc:IsFaceup() and not Duel.GetControl(tc,tp,PHASE_END,1) then
+	if tc and tc:IsRelateToEffect(e) and tc:IsFaceup() and not Duel.GetControl(tc,tp,PHASE_END,1) then
 		if not tc:IsImmuneToEffect(e) and tc:IsAbleToChangeControler() then
 			Duel.Destroy(tc,REASON_EFFECT)
 		end

script/c56981417.lua

@@ -53,7 +53,8 @@ function c56981417.target(e,tp,eg,ep,ev,re,r,rp,chk,chkc)
 end
 function c56981417.operation(e,tp,eg,ep,ev,re,r,rp)
 	local te=e:GetLabelObject()
-	if not te:GetHandler():IsRelateToEffect(e) then return end
-	local op=te:GetOperation()
-	if op then op(e,tp,eg,ep,ev,re,r,rp) end
+	if te and te:GetHandler():IsRelateToEffect(e) then  
+		local op=te:GetOperation()
+		if op then op(e,tp,eg,ep,ev,re,r,rp) end
+	end
 end

script/c56995655.lua

@@ -27,11 +27,13 @@ function c56995655.op(e,tp,eg,ep,ev,re,r,rp)
 	if not c:IsRelateToEffect(e) then return end
 	local g=Duel.GetFieldGroup(tp,0,LOCATION_HAND):RandomSelect(tp,1,nil)
 	local tc=g:GetFirst()
-	Duel.Hint(HINT_SELECTMSG,tp,HINTMSG_CARDTYPE)
-	local op=Duel.SelectOption(tp,70,71,72)
-	Duel.ConfirmCards(tp,tc)
-	Duel.ShuffleHand(1-tp)
-	if (op==0 and tc:IsType(TYPE_MONSTER)) or (op==1 and tc:IsType(TYPE_SPELL)) or (op==2 and tc:IsType(TYPE_TRAP)) then
-		Duel.Damage(1-tp,700,REASON_EFFECT)
+	if tc then
+		Duel.Hint(HINT_SELECTMSG,tp,HINTMSG_CARDTYPE)
+		local op=Duel.SelectOption(tp,70,71,72)
+		Duel.ConfirmCards(tp,tc)
+		Duel.ShuffleHand(1-tp)
+		if (op==0 and tc:IsType(TYPE_MONSTER)) or (op==1 and tc:IsType(TYPE_SPELL)) or (op==2 and tc:IsType(TYPE_TRAP)) then
+			Duel.Damage(1-tp,700,REASON_EFFECT)
+		end
 	end
 end

script/c5818294.lua

@@ -20,7 +20,7 @@ end
 function c5818294.negcon(e,tp,eg,ep,ev,re,r,rp)
 	if not re:IsHasProperty(EFFECT_FLAG_CARD_TARGET) then return false end
 	local g=Duel.GetChainInfo(ev,CHAININFO_TARGET_CARDS)
-	return g:IsExists(c5818294.tfilter,1,nil,tp)
+	return g and g:IsExists(c5818294.tfilter,1,nil,tp)
 end
 function c5818294.negcost(e,tp,eg,ep,ev,re,r,rp,chk)
 	if chk==0 then return e:GetHandler():IsAbleToRemoveAsCost() end

script/c68786330.lua

@@ -19,7 +19,7 @@ end
 function c68786330.poscon(e,tp,eg,ep,ev,re,r,rp)
 	local a=Duel.GetAttacker()
 	local d=Duel.GetAttackTarget()
-	return a:IsRelateToBattle() and d:IsRelateToBattle() and a:IsRace(RACE_REPTILE) and d:IsPosition(POS_DEFENCE)
+	return a and d and a:IsRelateToBattle() and d:IsRelateToBattle() and a:IsRace(RACE_REPTILE) and d:IsPosition(POS_DEFENCE)
 end
 function c68786330.posop(e,tp,eg,ep,ev,re,r,rp)
 	if not e:GetHandler():IsRelateToEffect(e) then return end

script/c71315423.lua

@@ -57,5 +57,8 @@ function c71315423.damtg(e,tp,eg,ep,ev,re,r,rp,chk)
 	Duel.SetOperationInfo(0,CATEGORY_DAMAGE,nil,0,e:GetHandler():GetEquipTarget():GetControler(),400)
 end
 function c71315423.damop(e,tp,eg,ep,ev,re,r,rp)
-	Duel.Damage(e:GetHandler():GetEquipTarget():GetControler(),400,REASON_EFFECT)
+	local tg=e:GetHandler():GetEquipTarget()
+	if tg then
+	Duel.Damage(tg:GetControler(),400,REASON_EFFECT)
+	end
 end

script/c73414375.lua

@@ -26,7 +26,9 @@ function c73414375.target(e,tp,eg,ep,ev,re,r,rp,chk,chkc)
 	if Duel.IsExistingTarget(c73414375.filter,1-tp,0,LOCATION_GRAVE,1,nil) and Duel.SelectYesNo(1-tp,aux.Stringid(73414375,1)) then
 		Duel.Hint(HINT_SELECTMSG,1-tp,HINTMSG_REMOVE)
 		local rg=Duel.SelectTarget(1-tp,c73414375.filter,1-tp,0,LOCATION_GRAVE,1,3,nil)
-		g:Merge(rg)
+		if rg then 
+			g:Merge(rg)
+		end
 	end
 	Duel.SetOperationInfo(0,CATEGORY_REMOVE,g,g:GetCount(),0,0)
 end

script/c88307361.lua

@@ -71,7 +71,7 @@ function c88307361.discon(e,tp,eg,ep,ev,re,r,rp)
 	if c:IsStatus(STATUS_BATTLE_DESTROYED) then return false end
 	if not re:IsHasProperty(EFFECT_FLAG_CARD_TARGET) then return end
 	local tg=Duel.GetChainInfo(ev,CHAININFO_TARGET_CARDS)
-	return tg:IsContains(c) and Duel.IsChainNegatable(ev)
+	return tg and tg:IsContains(c) and Duel.IsChainNegatable(ev)
 end
 function c88307361.discost(e,tp,eg,ep,ev,re,r,rp,chk)
 	if chk==0 then return Duel.CheckReleaseGroup(tp,Card.IsRace,1,e:GetHandler(),RACE_FISH) end

script/c99902789.lua

@@ -14,7 +14,9 @@ function c99902789.initial_effect(c)
 	c:RegisterEffect(e1)
 end
 function c99902789.discon(e,tp,eg,ep,ev,re,r,rp)
-	return Duel.CheckEvent(EVENT_ATTACK_ANNOUNCE) and Duel.GetAttacker():IsControler(tp) and Duel.GetAttackTarget()~=nil
+	local a=Duel.GetAttacker()
+	local at=Duel.GetAttackTarget()
+	return Duel.CheckEvent(EVENT_ATTACK_ANNOUNCE) and at and (a and a:IsControler(tp) or at:IsControler(tp))
 		and ep~=tp and re:GetActiveType()==TYPE_TRAP and re:IsHasType(EFFECT_TYPE_ACTIVATE) and Duel.IsChainNegatable(ev)
 end
 function c99902789.discost(e,tp,eg,ep,ev,re,r,rp,chk)