Oasis
Activate this card by targeting 1 monster in your Graveyard; Special Summon it in Defense Position. It becomes Wyrm-Type. When this card leaves the field, destroy that monster. When that monster leaves the field, destroy this card.
local s, id, o = GetID()
function s.initial_effect(c)
	--Activate
	local e1 = Effect.CreateEffect(c)
	e1:SetCategory(CATEGORY_SPECIAL_SUMMON)
	e1:SetType(EFFECT_TYPE_ACTIVATE)
	e1:SetCode(EVENT_FREE_CHAIN)
	e1:SetHintTiming(0, TIMING_END_PHASE)
	e1:SetProperty(EFFECT_FLAG_CARD_TARGET)
	e1:SetTarget(s.target)
	e1:SetOperation(s.operation)
	c:RegisterEffect(e1)
	--destroy
	local e2 = Effect.CreateEffect(c)
	e2:SetType(EFFECT_TYPE_CONTINUOUS + EFFECT_TYPE_SINGLE)
	e2:SetProperty(EFFECT_FLAG_CANNOT_DISABLE)
	e2:SetCode(EVENT_LEAVE_FIELD_P)
	e2:SetOperation(s.checkop)
	c:RegisterEffect(e2)
	local e3 = Effect.CreateEffect(c)
	e3:SetType(EFFECT_TYPE_CONTINUOUS + EFFECT_TYPE_SINGLE)
	e3:SetCode(EVENT_LEAVE_FIELD)
	e3:SetOperation(s.desop)
	e3:SetLabelObject(e2)
	c:RegisterEffect(e3)
	--destroy2
	local e4 = Effect.CreateEffect(c)
	e4:SetType(EFFECT_TYPE_CONTINUOUS + EFFECT_TYPE_FIELD)
	e4:SetRange(LOCATION_SZONE)
	e4:SetCode(EVENT_LEAVE_FIELD)
	e4:SetCondition(s.descon2)
	e4:SetOperation(s.desop2)
	c:RegisterEffect(e4)
	--change race
	local e5 = Effect.CreateEffect(c)
	e5:SetType(EFFECT_TYPE_TARGET)
	e5:SetCode(EFFECT_CHANGE_RACE)
	e5:SetRange(LOCATION_SZONE)
	e5:SetValue(RACE_WYRM)
	c:RegisterEffect(e5)
end
function s.filter(c, e, tp)
	return c:IsCanBeSpecialSummoned(e, 0, tp, false, false, POS_FACEUP_DEFENSE)
end
function s.target(e, tp, eg, ep, ev, re, r, rp, chk, chkc)
	if chkc then
		return chkc:IsLocation(LOCATION_GRAVE) and chkc:IsControler(tp) and s.filter(chkc, e, tp)
	end
	if chk == 0 then
		return Duel.GetLocationCount(tp, LOCATION_MZONE) > 0 and Duel.IsExistingTarget(s.filter, tp, LOCATION_GRAVE, 0, 1, nil, e, tp)
	end
	Duel.Hint(HINT_SELECTMSG, tp, HINTMSG_SPSUMMON)
	local g = Duel.SelectTarget(tp, s.filter, tp, LOCATION_GRAVE, 0, 1, 1, nil, e, tp)
	Duel.SetOperationInfo(0, CATEGORY_SPECIAL_SUMMON, g, 1, 0, 0)
end
function s.operation(e, tp, eg, ep, ev, re, r, rp)
	local c = e:GetHandler()
	local tc = Duel.GetFirstTarget()
	if c:IsRelateToEffect(e) and tc:IsRelateToEffect(e) and Duel.SpecialSummonStep(tc, 0, tp, tp, false, false, POS_FACEUP_DEFENSE) then
		c:SetCardTarget(tc)
	end
	Duel.SpecialSummonComplete()
end
function s.checkop(e, tp, eg, ep, ev, re, r, rp)
	if e:GetHandler():IsDisabled() then
		e:SetLabel(1)
	else
		e:SetLabel(0)
	end
end
function s.desop(e, tp, eg, ep, ev, re, r, rp)
	if e:GetLabelObject():GetLabel() ~= 0 then
		return
	end
	local tc = e:GetHandler():GetFirstCardTarget()
	if tc and tc:IsLocation(LOCATION_MZONE) then
		Duel.Destroy(tc, REASON_EFFECT)
	end
end
function s.descon2(e, tp, eg, ep, ev, re, r, rp)
	local tc = e:GetHandler():GetFirstCardTarget()
	return tc and eg:IsContains(tc)
end
function s.desop2(e, tp, eg, ep, ev, re, r, rp)
	Duel.Destroy(e:GetHandler(), REASON_EFFECT)
end


Oasis
Activate this card by targeting 1 monster in your Graveyard; Special Summon it in Defense Position. It becomes Wyrm-Type. When this card leaves the field, destroy that monster. When that monster leaves the field, destroy this card.
-- Oasis
local s, id, o = GetID()
function s.initial_effect(c)
	--Activate
	local e1 = Effect.CreateEffect(c)
	e1:SetCategory(CATEGORY_SPECIAL_SUMMON)
	e1:SetType(EFFECT_TYPE_ACTIVATE)
	e1:SetCode(EVENT_FREE_CHAIN)
	e1:SetHintTiming(0, TIMING_END_PHASE)
	e1:SetProperty(EFFECT_FLAG_CARD_TARGET)
	e1:SetTarget(s.target)
	e1:SetOperation(s.operation)
	c:RegisterEffect(e1)
	--destroy
	local e2 = Effect.CreateEffect(c)
	e2:SetType(EFFECT_TYPE_CONTINUOUS + EFFECT_TYPE_SINGLE)
	e2:SetProperty(EFFECT_FLAG_CANNOT_DISABLE)
	e2:SetCode(EVENT_LEAVE_FIELD_P)
	e2:SetOperation(s.checkop)
	c:RegisterEffect(e2)
	local e3 = Effect.CreateEffect(c)
	e3:SetType(EFFECT_TYPE_CONTINUOUS + EFFECT_TYPE_SINGLE)
	e3:SetCode(EVENT_LEAVE_FIELD)
	e3:SetOperation(s.desop)
	e3:SetLabelObject(e2)
	c:RegisterEffect(e3)
	--destroy2
	local e4 = Effect.CreateEffect(c)
	e4:SetType(EFFECT_TYPE_CONTINUOUS + EFFECT_TYPE_FIELD)
	e4:SetRange(LOCATION_SZONE)
	e4:SetCode(EVENT_LEAVE_FIELD)
	e4:SetCondition(s.descon2)
	e4:SetOperation(s.desop2)
	c:RegisterEffect(e4)
	--change race
	local e5 = Effect.CreateEffect(c)
	e5:SetType(EFFECT_TYPE_TARGET)
	e5:SetCode(EFFECT_CHANGE_RACE)
	e5:SetRange(LOCATION_SZONE)
	e5:SetValue(RACE_WYRM)
	c:RegisterEffect(e5)
end
function s.filter(c, e, tp)
	return c:IsCanBeSpecialSummoned(e, 0, tp, false, false, POS_FACEUP_DEFENSE)
end
function s.target(e, tp, eg, ep, ev, re, r, rp, chk, chkc)
	if chkc then
		return chkc:IsLocation(LOCATION_GRAVE) and chkc:IsControler(tp) and s.filter(chkc, e, tp)
	end
	if chk == 0 then
		return Duel.GetLocationCount(tp, LOCATION_MZONE) > 0 and Duel.IsExistingTarget(s.filter, tp, LOCATION_GRAVE, 0, 1, nil, e, tp)
	end
	Duel.Hint(HINT_SELECTMSG, tp, HINTMSG_SPSUMMON)
	local g = Duel.SelectTarget(tp, s.filter, tp, LOCATION_GRAVE, 0, 1, 1, nil, e, tp)
	Duel.SetOperationInfo(0, CATEGORY_SPECIAL_SUMMON, g, 1, 0, 0)
end
function s.operation(e, tp, eg, ep, ev, re, r, rp)
	local c = e:GetHandler()
	local tc = Duel.GetFirstTarget()
	if c:IsRelateToEffect(e) and tc:IsRelateToEffect(e) and Duel.SpecialSummonStep(tc, 0, tp, tp, false, false, POS_FACEUP_DEFENSE) then
		c:SetCardTarget(tc)
	end
	Duel.SpecialSummonComplete()
end
function s.checkop(e, tp, eg, ep, ev, re, r, rp)
	if e:GetHandler():IsDisabled() then
		e:SetLabel(1)
	else
		e:SetLabel(0)
	end
end
function s.desop(e, tp, eg, ep, ev, re, r, rp)
	if e:GetLabelObject():GetLabel() ~= 0 then
		return
	end
	local tc = e:GetHandler():GetFirstCardTarget()
	if tc and tc:IsLocation(LOCATION_MZONE) then
		Duel.Destroy(tc, REASON_EFFECT)
	end
end
function s.descon2(e, tp, eg, ep, ev, re, r, rp)
	local tc = e:GetHandler():GetFirstCardTarget()
	return tc and eg:IsContains(tc)
end
function s.desop2(e, tp, eg, ep, ev, re, r, rp)
	Duel.Destroy(e:GetHandler(), REASON_EFFECT)
end

