Adding triggered abilities to spells as they're cast

[duncancmt]

I'm trying to implement Wort, the Raidmother (and I figure that I'll go ahead and implement Djinn Illuminatus and Thrumming Stone while I'm at it). After looking at Mycosynth Golem and Chief Engineer as examples, it seems like the correct approach is to abuse the replacement effect API to modify the spell as it goes on the stack. (this seems like the wrong approach because there's no way to track the layer that this effect belongs in, but I don't see any other way to do it) However, when I do something similar with Wort, it seems that the trigger gets lost in between adding the ability to the spell and triggers being checked. I added some functionality to the Conspire ability to export the trigger that it adds to spells and then explicitly added that trigger to the game state. When the SPELL_CAST event happens at the end of spell casting, my new trigger has been removed from the GameState's triggers.

Any idea what's going on here? Thanks!

[jeffwadsworth]

I could write a book about my foray into Wort land, but let me give a brief summary of the saga. I got it to the point where the Conspire ability was on the card while it was on the stack, but the Conspire trigger refused to work. I tried all kinds of ways to work around the issue, but to no avail. I hope you can work it out. Also, I put your code into the code brackets for easier reading.

Code: Select all

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package mage.sets.shadowmoor;

import java.util.UUID;
import mage.MageInt;
import mage.MageObject;
import mage.ObjectColor;
import mage.abilities.Ability;
import mage.abilities.TriggeredAbility;
import mage.constants.CardType;
import mage.constants.Rarity;

import mage.abilities.common.EntersBattlefieldTriggeredAbility;
import mage.abilities.common.SimpleStaticAbility;
import mage.abilities.effects.ReplacementEffectImpl;
import mage.abilities.effects.common.CreateTokenEffect;
import mage.abilities.keyword.ConspireAbility;
import mage.cards.Card;
import mage.cards.CardImpl;
import mage.constants.Duration;
import mage.constants.Outcome;
import mage.constants.Zone;
import mage.game.Game;
import mage.game.events.GameEvent;
import mage.game.permanent.token.Token;

/**
 * @author duncant
 */
public class WortTheRaidmother extends CardImpl {

    public WortTheRaidmother(UUID ownerId) {
        super(ownerId, 223, "Wort, the Raidmother", Rarity.RARE, new CardType[]{CardType.CREATURE}, "{4}{R/G}{R/G}");
        this.expansionSetCode = "SHM";
        this.supertype.add("Legendary");
        this.subtype.add("Goblin");
        this.subtype.add("Shaman");
        this.power = new MageInt(3);
        this.toughness = new MageInt(3);

        // When Wort, the Raidmother enters the battlefield, put two 1/1 red and green Goblin Warrior creature tokens onto the battlefield.
        this.addAbility(new EntersBattlefieldTriggeredAbility(new CreateTokenEffect(new WortTheRaidmotherToken(), 2), false));

        // Each red or green instant or sorcery spell you cast has conspire.
        this.addAbility(new SimpleStaticAbility(Zone.BATTLEFIELD, new AddConspireEffect()));
    }

    public WortTheRaidmother(final WortTheRaidmother card) {
        super(card);
    }

    @Override
    public WortTheRaidmother copy() {
        return new WortTheRaidmother(this);
    }
}

class AddConspireEffect extends ReplacementEffectImpl {

    public AddConspireEffect() {
        super(Duration.WhileOnBattlefield, Outcome.AddAbility);
        staticText = "Each red or green instant or sorcery spell you cast has conspire. <i>(As you cast the spell, you may tap two untapped creatures you control that share a color with it. When you do, copy it and you may choose new targets for the copy.)</i>";
    }

    public AddConspireEffect(final AddConspireEffect effect) {
        super(effect);
    }

    @Override
    public AddConspireEffect copy() {
        return new AddConspireEffect(this);
    }

    @Override
    public boolean apply(Game game, Ability source) {
        return true;
    }

    @Override
    public boolean replaceEvent(GameEvent event, Ability source, Game game) {
        Card card = (Card)game.getObject(event.getSourceId());
        if (card != null) {
            ConspireAbility ability = new ConspireAbility(card);
            card.addAbility(ability);
            ability.setControllerId(source.getControllerId());
            ability.setSourceId(card.getId());
            game.getState().addAbility(ability, source.getSourceId(), card);
            TriggeredAbility trigger = ability.getTrigger();
            trigger.setControllerId(source.getControllerId());
            trigger.setSourceId(card.getId());
            game.getState().addAbility(trigger, source.getSourceId(), card);
        }
        return false;
    }

    @Override
    public boolean checksEventType(GameEvent event, Game game) {
        return event.getType() == GameEvent.EventType.CAST_SPELL;
    }

    @Override
    public boolean applies(GameEvent event, Ability source, Game game) {
        if ((event.getType() == GameEvent.EventType.CAST_SPELL)
            && event.getPlayerId() == source.getControllerId()) {
            MageObject spellObject = game.getObject(event.getSourceId());
            if (spellObject != null &&
                (spellObject.getColor().contains(ObjectColor.RED) ||
                 spellObject.getColor().contains(ObjectColor.GREEN)) &&
                (spellObject.getCardType().contains(CardType.INSTANT) ||
                 spellObject.getCardType().contains(CardType.SORCERY))) {
                return true;
            }
        }
        return false;
    }
}


class WortTheRaidmotherToken extends Token {

    public WortTheRaidmotherToken() {
        super("Goblin Warrior", "1/1 red and green Goblin Warrior creature token");
        cardType.add(CardType.CREATURE);
        color.setRed(true);
        color.setGreen(true);
        subtype.add("Goblin");
        subtype.add("Warrior");
        power = new MageInt(1);
        toughness = new MageInt(1);
    }
}


[duncancmt]

I might try my hand with tweaking the larger architecture to support this kind of effect, because as it is now, there are 3 cards that can't be implemented at all (Wort, the Raidmother, Djinn Illuminatus, and Thrumming Stone) and 2 others (Chief Engineer, Mycosynth Golem) that are implemented "wrong" because their effects don't interface with the layers system.

If you still have access to your old Wort, the Raidmother code, I'd love to see it so that I can avoid your pitfalls.

[jeffwadsworth]

Take a look at the recently done Narset Transcendent by LevelX. Of course, the Conspire ability is different due to the passing of the card object, but it may help.