Add Terror of the Peaks

lib/magic/cards/terror_of_the_peaks.rb

@@ -0,0 +1,62 @@
+module Magic
+  module Cards
+    TerrorOfThePeaks = Creature("Terror of the Peaks") do
+      cost generic: 3, red: 2
+      creature_type "Dragon"
+      keywords :flying
+      power 5
+      toughness 4
+    end
+
+    class TerrorOfThePeaks < Creature
+      class WardTrigger < TriggeredAbility
+        def should_perform?
+          opponents.include?(event.player) && event.targets.include?(actor)
+        end
+
+        def call
+          trigger_effect(:lose_life, target: event.player, life: 3)
+        end
+      end
+
+      class CreatureEnteredTrigger < TriggeredAbility::EnterTheBattlefield
+        def should_perform?
+          another_creature? && under_your_control?
+        end
+
+        def call
+          game.choices.add(TerrorOfThePeaks::DamageChoice.new(
+            actor: actor,
+            power: event.permanent.power
+          ))
+        end
+      end
+
+      class DamageChoice < Magic::Choice::Targeted
+        def initialize(actor:, power:)
+          super(actor: actor)
+          @power = power
+        end
+
+        def choices
+          game.any_target
+        end
+
+        def choice_amount
+          1
+        end
+
+        def resolve!(target:)
+          trigger_effect(:deal_damage, damage: @power, target: target)
+        end
+      end
+
+      def event_handlers
+        {
+          Events::SpellCast => WardTrigger,
+          Events::EnteredTheBattlefield => CreatureEnteredTrigger
+        }
+      end
+    end
+  end
+end

spec/cards/terror_of_the_peaks_spec.rb

@@ -0,0 +1,68 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe Magic::Cards::TerrorOfThePeaks do
+  include_context "two player game"
+
+  let!(:terror) { ResolvePermanent("Terror Of The Peaks", owner: p1) }
+
+  it "is a 5/4 flying dragon" do
+    expect(terror.power).to eq(5)
+    expect(terror.toughness).to eq(4)
+    expect(terror).to be_flying
+    expect(terror.card.types).to include("Dragon")
+  end
+
+  context "when an opponent casts a spell targeting it" do
+    before do
+      p2.add_mana(red: 1)
+      action = cast_action(card: Card("Lightning Bolt", owner: p2), player: p2)
+      action.pay_mana(red: 1)
+      action.targeting(terror)
+      game.take_action(action)
+    end
+
+    it "the opponent loses 3 life" do
+      expect(p2.life).to eq(17)
+    end
+  end
+
+  context "when the controller casts a spell targeting it" do
+    before do
+      p1.add_mana(red: 2)
+      action = cast_action(card: Card("Sure Strike", owner: p1), player: p1)
+      action.pay_mana(generic: { red: 1 }, red: 1)
+      action.targeting(terror)
+      game.take_action(action)
+    end
+
+    it "the controller does not lose life" do
+      expect(p1.life).to eq(20)
+    end
+  end
+
+  context "when another creature you control enters" do
+    let!(:wood_elves) { ResolvePermanent("Wood Elves", owner: p1) }
+
+    it "adds a damage choice targeting any target" do
+      choice = game.choices.first
+      expect(choice).to be_a(described_class::DamageChoice)
+      expect(choice.choices).to include(p2)
+      expect(choice.choices).to include(wood_elves)
+    end
+
+    it "deals damage equal to the entering creature's power to the chosen target" do
+      game.resolve_choice!(target: p2)
+      expect(p2.life).to eq(19) # Wood Elves power = 1
+    end
+  end
+
+  context "when an opponent's creature enters" do
+    let!(:wood_elves) { ResolvePermanent("Wood Elves", owner: p2) }
+
+    it "does not trigger" do
+      expect(game.choices).to be_empty
+    end
+  end
+end