diff --git a/src/main/scala/wordbots/AstValidator.scala b/src/main/scala/wordbots/AstValidator.scala
index 566b75f..7972ec5 100644
--- a/src/main/scala/wordbots/AstValidator.scala
+++ b/src/main/scala/wordbots/AstValidator.scala
@@ -80,7 +80,7 @@ object NoUnimplementedRules extends AstRule {
 }
 
 /**
- * Disallow the following behaviors within a triggered ability (excepted AfterPlayed, which can be treated more like an action):
+ * Disallow the following behaviors within a triggered ability or conditional action (except AfterPlayed trigger, which can be treated more like an action):
  *    * choosing targets (because there's no UI support for having a player choose targets during event execution)
  *    * rewriting card text (because calling the parser is expensive and should only happen from direct player interaction)
  */
@@ -101,13 +101,14 @@ object NoChooseOrRewriteInTriggeredAction extends AstRule {
     node match {
       case TriggeredAbility(AfterPlayed(_), _) => Success()  // Choosing targets and rewriting text *is* allowed for AfterPlayed triggers.
       case TriggeredAbility(_, _) => validateChildren(NoChooseTargetOrRewrite, node)  // (but not for any other trigger).
+      case ConditionalAction(_, _) => validateChildren(NoChooseTargetOrRewrite, node)
       case n: AstNode => validateChildren(this, n)
     }
   }
 }
 
 /**
- * Disallow paying energy within triggered abilities,
+ * Disallow paying energy within triggered abilities or conditional actions,
  * because there's no gameplay support for "rolling back" the action triggered if there's not enough energy to pay.
  */
 object NoPayEnergyInTriggeredAction extends AstRule {
@@ -123,6 +124,7 @@ object NoPayEnergyInTriggeredAction extends AstRule {
   override def validate(node: AstNode): Try[Unit] = {
     node match {
       case TriggeredAbility(_, _) => validateChildren(NoPayEnergy, node)
+      case ConditionalAction(_, _) => validateChildren(NoPayEnergy, node)
       case n: AstNode => validateChildren(this, n)
     }
   }
diff --git a/src/main/scala/wordbots/ErrorAnalyzer.scala b/src/main/scala/wordbots/ErrorAnalyzer.scala
index cf15f31..c13a4e0 100644
--- a/src/main/scala/wordbots/ErrorAnalyzer.scala
+++ b/src/main/scala/wordbots/ErrorAnalyzer.scala
@@ -1,7 +1,7 @@
 package wordbots
 
 import com.workday.montague.ccg.CcgCat
-import com.workday.montague.parser.SemanticParseNode
+import com.workday.montague.parser.{SemanticParseNode, SemanticParseResult}
 import com.workday.montague.semantics.{Form, Lambda, Nonsense}
 import scalaz.Memo
 
@@ -58,6 +58,20 @@ object ErrorAnalyzer {
     (result, t1 - t0)
   }
 
+  /** If any parses are semantically complete, selects the first one that passes AstValidator. Otherwise, selects bestParse (if any) as determined by the parser. */
+  def bestValidParse(parseResult: SemanticParseResult[CcgCat])(implicit validationMode: ValidationMode = ValidateUnknownCard): Option[SemanticParseNode[CcgCat]] = {
+    val bestValidParses: List[SemanticParseNode[CcgCat]] = for {
+      parse <- parseResult.semanticCompleteParses
+      ast <- parse.semantic match {
+        case Form(ast: AstNode) => Some(ast)
+        case _ => None
+      }
+      if AstValidator(validationMode).validate(ast).isSuccess
+    } yield parse
+
+    bestValidParses.headOption.orElse(parseResult.bestParse)
+  }
+
   // Note: "fast mode" disables finding syntax/semantics suggestions and just does the bare minimum to diagnose the error
   def diagnoseError(input: String, parseResult: Option[SemanticParseNode[CcgCat]], isFastMode: Boolean = false)
                    (implicit validationMode: ValidationMode = ValidateUnknownCard): Option[ParserError] = {
diff --git a/src/main/scala/wordbots/Lexicon.scala b/src/main/scala/wordbots/Lexicon.scala
index 407a861..f2c85e9 100644
--- a/src/main/scala/wordbots/Lexicon.scala
+++ b/src/main/scala/wordbots/Lexicon.scala
@@ -71,11 +71,13 @@ object Lexicon {
       ((NP/NP)\N, λ {o: ObjectType => λ {t: TargetObjectOrTile => ObjectsMatchingConditions(o, Seq(AdjacentTo(t)))}}),
       (PP/NP, λ {c: ObjectsMatchingConditions => ObjectsMatchingConditions(c.objectType, Seq(AdjacentTo(ThisObject)) ++ c.conditions)})
     )) +
-    ("is" /?/ Seq("adjacent to", "adjacent to a", "adjacent to an") -> Seq(
+    ("is" / Seq("adjacent to", "adjacent to a", "adjacent to an") -> Seq(
+      ((S\NP)/N, λ {t: ObjectType => λ {o: TargetObject => CollectionExists(ObjectsMatchingConditions(t, Seq(AdjacentTo(o))))}}),
       ((S\N)/NP, λ {o: TargetObject => λ {e: EnemyObject => CollectionExists(ObjectsMatchingConditions(e.objectType, Seq(AdjacentTo(o), ControlledBy(Opponent))))}}),
       ((S\NP)/NP, λ {c: ObjectsMatchingConditions => λ {o: TargetObject => CollectionExists(ObjectsMatchingConditions(c.objectType, c.conditions :+ AdjacentTo(o)))}})
     )) +
-    ("is not" /?/ Seq("adjacent to", "adjacent to a", "adjacent to an") -> Seq(
+    ("is not" / Seq("adjacent to", "adjacent to a", "adjacent to an") -> Seq(
+      ((S\NP)/N, λ {t: ObjectType => λ {o: TargetObject => NotGC(CollectionExists(ObjectsMatchingConditions(t, Seq(AdjacentTo(o)))))}}),
       ((S\N)/NP, λ {o: TargetObject => λ {e: EnemyObject => NotGC(CollectionExists(ObjectsMatchingConditions(e.objectType, Seq(AdjacentTo(o), ControlledBy(Opponent)))))}}),
       ((S\NP)/NP, λ {c: ObjectsMatchingConditions => λ {o: TargetObject => NotGC(CollectionExists(ObjectsMatchingConditions(c.objectType, c.conditions :+ AdjacentTo(o))))}})
     )) +
diff --git a/src/main/scala/wordbots/Parser.scala b/src/main/scala/wordbots/Parser.scala
index 6dec20c..6497f22 100644
--- a/src/main/scala/wordbots/Parser.scala
+++ b/src/main/scala/wordbots/Parser.scala
@@ -1,7 +1,7 @@
 package wordbots
 
 import com.workday.montague.ccg._
-import com.workday.montague.parser.{ParserDict, SemanticParseResult, SemanticParser}
+import com.workday.montague.parser.{ParserDict, SemanticParseNode, SemanticParseResult, SemanticParser}
 import com.workday.montague.semantics._
 
 import scala.language.postfixOps
@@ -18,8 +18,11 @@ object Parser extends SemanticParser[CcgCat](Lexicon.lexicon) {
     val input = args.mkString(" ")
     val result: SemanticParseResult[CcgCat] = parse(input)
 
-    val output: String = result.bestParse.map(p => s"${p.semantic.toString} [${p.syntactic.toString}]").getOrElse("(failed to parse)")
-    val code: Try[String] = Try { result.bestParse.get.semantic }.flatMap {
+    val bestParse: Option[SemanticParseNode[CcgCat]] = ErrorAnalyzer.bestValidParse(result)
+    val allSemanticallyCompleteParses: List[String] = result.semanticCompleteParses.map(p => s"${p.semantic.toString} [${p.syntactic.toString}]")
+
+    val output: String = bestParse.map(p => s"${p.semantic.toString} [${p.syntactic.toString}]").getOrElse("(failed to parse)")
+    val code: Try[String] = Try { bestParse.get.semantic }.flatMap {
       case Form(v: Semantics.AstNode) => CodeGenerator.generateJS(v)
       case _ => Failure(new RuntimeException("Parser did not produce a valid expression"))
     }
@@ -28,12 +31,13 @@ object Parser extends SemanticParser[CcgCat](Lexicon.lexicon) {
     println(s"Input: $input")
     println(s"Tokens: ${tokenizer(input).mkString("[\"", "\", \"", "\"]")}")
     println(s"Parse result: $output")
-    println(s"Error diagnosis: ${ErrorAnalyzer.diagnoseError(input, result.bestParse)}")
+    println(s"All semantically complete parse results:\n  ${allSemanticallyCompleteParses.mkString("\n  ")}")
+    println(s"Error diagnosis: ${ErrorAnalyzer.diagnoseError(input, bestParse)}")
     println(s"Generated JS code: ${code.getOrElse(code.failed.get)}")
     // scalastyle:on regex
 
     // For debug purposes, output the best parse tree (if one exists) to SVG.
-    //result.bestParse.foreach(result => new java.io.PrintWriter("test.svg") { write(result.toSvg); close() })
+    //bestParse.foreach(result => new java.io.PrintWriter("test.svg") { write(result.toSvg); close() })
   }
 
   /** Parses the input. */
diff --git a/src/main/scala/wordbots/Server.scala b/src/main/scala/wordbots/Server.scala
index 4acbe4f..5d38016 100644
--- a/src/main/scala/wordbots/Server.scala
+++ b/src/main/scala/wordbots/Server.scala
@@ -2,7 +2,7 @@ package wordbots
 
 import com.roundeights.hasher.Implicits._
 import com.workday.montague.ccg.CcgCat
-import com.workday.montague.parser.SemanticParseNode
+import com.workday.montague.parser.{SemanticParseNode, SemanticParseResult}
 import com.workday.montague.semantics.{Form, SemanticState}
 import org.http4s.{Response => H4sResponse, _}
 import org.http4s.circe._
@@ -12,6 +12,7 @@ import org.http4s.server.blaze.BlazeBuilder
 import io.circe._
 import io.circe.generic.auto._
 import io.circe.syntax._
+import org.log4s.MDC.result
 import scalaz.Memo
 import scalaz.concurrent.Task
 import wordbots.Semantics.AstNode
@@ -51,25 +52,26 @@ object MemoParser {
       case _ => ValidateUnknownCard
     }
 
-    val result = Parser.parse(input).bestParse
-    val parsedTokens = {
-      result.toSeq
+    val parseResult: SemanticParseResult[CcgCat] = Parser.parse(input)
+    val bestParse: Option[SemanticParseNode[CcgCat]] = ErrorAnalyzer.bestValidParse(parseResult)
+    val parsedTokens: Seq[String] = {
+      bestParse.toSeq
         .flatMap(_.terminals)
         .flatMap(_.parseTokens)
         .map(_.tokenString)
         .filter(token => Lexicon.listOfTerms.contains(token) && token != "\"")
     }
-    val unrecognizedTokens = ErrorAnalyzer.findUnrecognizedTokens(input)
+    val unrecognizedTokens: Seq[String] = ErrorAnalyzer.findUnrecognizedTokens(input)
 
-    ErrorAnalyzer.diagnoseError(input, result, fastErrorAnalysisMode) match {
+    ErrorAnalyzer.diagnoseError(input, bestParse, fastErrorAnalysisMode) match {
       case Some(error) =>
         print("  [F]")
         FailedParse(error, unrecognizedTokens)
       case None =>
-        result.map(_.semantic) match {
+        bestParse.map(_.semantic) match {
           case Some(Form(ast: AstNode)) =>
             print("  [S]")
-            SuccessfulParse(result.get, ast, parsedTokens)
+            SuccessfulParse(bestParse.get, ast, parsedTokens)
           case _ =>
             print("  [F]")
             FailedParse(ParserError("Unspecified parser error"), unrecognizedTokens)
diff --git a/src/test/scala/wordbots/ErrorAnalyzerSpec.scala b/src/test/scala/wordbots/ErrorAnalyzerSpec.scala
index 3101a51..7f8ada0 100644
--- a/src/test/scala/wordbots/ErrorAnalyzerSpec.scala
+++ b/src/test/scala/wordbots/ErrorAnalyzerSpec.scala
@@ -4,7 +4,7 @@ import org.scalatest._
 
 class ErrorAnalyzerSpec extends FlatSpec with Matchers {
   def analyze(input: String): Option[ParserError] = {
-    val parseResult = Parser.parse(input).bestParse
+    val parseResult = ErrorAnalyzer.bestValidParse(Parser.parse(input))
     ErrorAnalyzer.diagnoseError(input, parseResult)
   }
 
diff --git a/src/test/scala/wordbots/ParserSpec.scala b/src/test/scala/wordbots/ParserSpec.scala
index f0fcef7..f9cd153 100644
--- a/src/test/scala/wordbots/ParserSpec.scala
+++ b/src/test/scala/wordbots/ParserSpec.scala
@@ -13,7 +13,7 @@ class ParserSpec extends FlatSpec with Matchers {
   //scalastyle:off regex
   def parse(input: String, validationMode: ValidationMode = ValidateUnknownCard): Any = {
     println(s"Parsing $input...")
-    Parser.parse(input).bestParse match {
+    ErrorAnalyzer.bestValidParse(Parser.parse(input)) match {
       case Some(parse) => parse.semantic match {
         case Form(v: AstNode) =>
           println(s"    $v")
@@ -424,8 +424,12 @@ class ParserSpec extends FlatSpec with Matchers {
       TriggeredAbility(AfterDestroyed(ThisObject), DealDamage(ObjectsMatchingConditions(AllObjects, Seq(WithinDistanceOf(Scalar(2), ThisObject))), Scalar(2)))
 
     //scalastyle:off magic.number
-    parse("When this robot is played, if it is adjacent to an enemy robot, it gains 5 health.") shouldEqual
-      TriggeredAbility(AfterPlayed(ThisObject), If(CollectionExists(ObjectsMatchingConditions(Robot, List(ControlledBy(Opponent), AdjacentTo(ItO)))), ModifyAttribute(ItO, Health, Plus(Scalar(5)))))
+    // (two possible parses here, both valid and both achieving the same result)
+    parse("When this robot is played, if it is adjacent to an enemy robot, it gains 5 health.") should (
+      equal(TriggeredAbility(AfterPlayed(ThisObject), If(CollectionExists(ObjectsMatchingConditions(Robot, List(ControlledBy(Opponent), AdjacentTo(ItO)))), ModifyAttribute(ItO, Health, Plus(Scalar(5))))))
+      or equal(TriggeredAbility(AfterPlayed(ThisObject), If(TargetMeetsCondition(ItO, AdjacentTo(ChooseO(ObjectsMatchingConditions(Robot, List(ControlledBy(Opponent))), Scalar(1)))), ModifyAttribute(ItO, Health, Plus(Scalar(5))))))
+    )
+
     //scalastyle:on magic.number
     parse("When this robot attacks, it can attack again.") shouldEqual
       TriggeredAbility(AfterAttack(ThisObject), CanAttackAgain(ItO))