- Some logic update for Krav. Somewhat better handling of CostSacrifice inside DrawAi.

forge-ai/src/main/java/forge/ai/AiCostDecision.java

@@ -514,14 +514,18 @@ public class AiCostDecision extends CostDecisionMakerBase {
         Integer c = cost.convertAmount();
         if (c == null) {
             if (ability.getSVar(cost.getAmount()).equals("XChoice")) {
-                if ("SacToReduceCost".equals(ability.getParam("AILogic"))) {
+                String logic = ability.getParamOrDefault("AILogic", "");
+                if ("SacToReduceCost".equals(logic)) {
                     // e.g. Torgaar, Famine Incarnate
                     // TODO: currently returns an empty list, so the AI doesn't sacrifice anything. Trying to make
                     // the AI decide on creatures to sac makes the AI sacrifice them, but the cost is not reduced and the
                     // AI pays the full mana cost anyway (despite sacrificing creatures).
                     return PaymentDecision.card(new CardCollection());
-                } else if ("AsChosen".equals(ability.getParam("AILogic"))) {
+                } else if (!logic.isEmpty() && !logic.equals("Never")) {
-                    // Honor the ChosenX value set earlier by the AI ability processing code.
+                    // If at least some other AI logic is specified, assume that the AI for that API knows how
+                    // to define ChosenX and thus honor that value.
+                    // Cards which have no special logic for this yet but which do work in a simple/suboptimal way
+                    // are currently conventionally flagged with AILogic$ DoSacrifice.
                     c = AbilityUtils.calculateAmount(source, source.getSVar("ChosenX"), null);
                 } else {
                     // Other cards are assumed to be flagged RemAIDeck for now

forge-ai/src/main/java/forge/ai/ability/DrawAi.java

@@ -26,10 +26,7 @@ import forge.game.card.Card;
 import forge.game.card.CardLists;
 import forge.game.card.CardPredicates;
 import forge.game.card.CounterType;
-import forge.game.cost.Cost;
+import forge.game.cost.*;
-import forge.game.cost.CostDiscard;
-import forge.game.cost.CostPart;
-import forge.game.cost.PaymentDecision;
 import forge.game.phase.PhaseHandler;
 import forge.game.phase.PhaseType;
 import forge.game.player.Player;
@@ -252,22 +249,32 @@ public class DrawAi extends SpellAbilityAi {
         }
 
         if (num != null && num.equals("ChosenX")) {
-            // Necrologia, Pay X Life : Draw X Cards
             if (sa.getSVar("X").equals("XChoice")) {
                 // Draw up to max hand size but leave at least 3 in library
                 numCards = Math.min(computerMaxHandSize - computerHandSize, computerLibrarySize - 3);
-                // But no more than what's "safe" and doesn't risk a near death experience
+
-                // Maybe would be better to check for "serious danger" and take more risk?
+                if (sa.getPayCosts() != null) {
-                while ((ComputerUtil.aiLifeInDanger(ai, false, numCards) && (numCards > 0))) {
+                    if (sa.getPayCosts().hasSpecificCostType(CostPayLife.class)) {
-                    numCards--;
+                        // [Necrologia, Pay X Life : Draw X Cards]
+                        // Don't draw more than what's "safe" and don't risk a near death experience
+                        // Maybe would be better to check for "serious danger" and take more risk?
+                        while ((ComputerUtil.aiLifeInDanger(ai, false, numCards) && (numCards > 0))) {
+                            numCards--;
+                        }
+                    } else if (sa.getPayCosts().hasSpecificCostType(CostSacrifice.class)) {
+                        // [e.g. Krav, the Unredeemed and other cases which say "Sacrifice X creatures: draw X cards]
+                        // TODO: Add special logic to limit/otherwise modify the ChosenX value here
+
+                        // Skip this ability if nothing is to be chosen for sacrifice
+                        if (numCards <= 0) {
+                            return false;
+                        }
+                    }
                 }
+
                 sa.setSVar("ChosenX", Integer.toString(numCards));
                 source.setSVar("ChosenX", Integer.toString(numCards));
 
-                // If the logic is set to AsChosen, then skip the ability if nothing is to be chosen
-                if ("AsChosen".equals(sa.getParam("AILogic")) && numCards <= 0) {
-                    return false;
-                }
             }
         }
         // Logic for cards that require special handling

forge-gui/res/cardsfolder/upcoming/krav_the_unredeemed.txt

@@ -3,7 +3,9 @@ ManaCost:4 B
 Types:Legendary Creature Demon
 PT:3/3
 K:Partner:Regna, the Redeemer:Regna
-A:AB$Draw | Cost$ B Sac<X/Creature/creatures> | NumCards$ ChosenX | ValidTgts$ Player | TgtPrompt$ Choose a player | References$ X | SubAbility$ DBGainLife | AILogic$ AsChosen | SpellDescription$ Target player draws X cards and gains X life. Put X +1/+1 counters on CARDNAME.
+# TODO: AILogic$ DoSacrifice is a placeholder which signals AiCostDecision that the API knows how to properly determine
+# the number of creatures to sacrifice. Currently DrawAi doesn't handle it too optimally and this can be improved.
+A:AB$Draw | Cost$ B Sac<X/Creature/creatures> | NumCards$ ChosenX | ValidTgts$ Player | TgtPrompt$ Choose a player | References$ X | SubAbility$ DBGainLife | AILogic$ DoSacrifice | SpellDescription$ Target player draws X cards and gains X life. Put X +1/+1 counters on CARDNAME.
 SVar:DBGainLife:DB$GainLife | Defined$ Targeted | LifeAmount$ ChosenX | SubAbility$ DBPutCounter
 SVar:DBPutCounter:DB$PutCounter | Defined$ Self | CounterType$ P1P1 | CounterNum$ ChosenX
 SVar:X:XChoice