Call of the Shadow NOVA Script (Written by chatgpt)

-- Call of the Shadow NOVA
local s, id = GetID(19822)

function s.initial_effect(c)
    -- Activate
    local e1 = Effect.CreateEffect(c)
    e1:SetCategory(CATEGORY_TOHAND + CATEGORY_SEARCH)
    e1:SetType(EFFECT_TYPE_ACTIVATE)
    e1:SetCode(EVENT_FREE_CHAIN)
    e1:SetCountLimit(1, id)
    e1:SetTarget(s.activate)
    e1:SetOperation(s.activate)
    c:RegisterEffect(e1)

    -- GY effect
    local e2 = Effect.CreateEffect(c)
    e2:SetCategory(CATEGORY_TOHAND + CATEGORY_SEARCH)
    e2:SetType(EFFECT_TYPE_FIELD + EFFECT_TYPE_TRIGGER_F)
    e2:SetCode(EVENT_PHASE + PHASE_END)
    e2:SetRange(LOCATION_GRAVE)
    e2:SetCountLimit(1, id+100)
    e2:SetCondition(s.gyCondition)
    e2:SetTarget(s.gyTarget)
    e2:SetOperation(s.gyOperation)
    c:RegisterEffect(e2)
end

function s.filter(c)
    return c:IsSetCard(0x123) and c:IsAbleToHand()
end

function s.activate(e, tp, eg, ep, ev, re, r, rp)
    if not e:GetHandler():IsRelateToEffect(e) then
        return
    end

    local g = Duel.GetMatchingGroup(s.filter, tp, LOCATION_DECK, 0, nil)
    if g:GetCount() > 0 and Duel.SelectYesNo(tp, aux.Stringid(id, 0)) then
        Duel.Hint(HINT_SELECTMSG, tp, HINTMSG_ATOHAND)
        local sg = g:Select(tp, 1, 1, nil)
        Duel.SendtoHand(sg, nil, REASON_EFFECT)
        Duel.ConfirmCards(1 - tp, sg)
        e:SetLabel(1) -- Set a flag to indicate the activation of the first effect
    end
end

function s.gyCondition(e, tp, eg, ep, ev, re, r, rp)
    return Duel.GetTurnPlayer() ~= tp and e:GetHandler():IsPreviousLocation(LOCATION_ONFIELD)
end

function s.gyTarget(e, tp, eg, ep, ev, re, r, rp, chk)
    if chk == 0 then
        return Duel.IsExistingMatchingCard(s.filter, tp, LOCATION_DECK, 0, 1, nil)
    end
    Duel.SetOperationInfo(0, CATEGORY_TOHAND, nil, 1, tp, LOCATION_DECK)
end

function s.gyOperation(e, tp, eg, ep, ev, re, r, rp)
    if not e:GetHandler():IsRelateToEffect(e) then
        return
    end

    if e:GetLabel() == 1 then
        e:SetLabel(0) -- Reset the flag
        return
    end

    local g = Duel.GetMatchingGroup(s.filter, tp, LOCATION_DECK, 0, nil)
    if g:GetCount() > 0 then
        Duel.Hint(HINT_SELECTMSG, tp, HINTMSG_ATOHAND)
        local sg = g:Select(tp, 1, 1, nil)
        Duel.SendtoHand(sg, nil, REASON_EFFECT)
        Duel.ConfirmCards(1 - tp, sg)
    end
end