diff --git a/cardsim/player.go b/cardsim/player.go
index 539a780..a5a15e9 100644
--- a/cardsim/player.go
+++ b/cardsim/player.go
@@ -423,3 +423,31 @@ func (p *Player[C]) EnactPermanentAction(actionIdx, choiceIdx int) (Message, err
 	}
 	return p.EnactPermanentActionUnchecked(actionIdx, choiceIdx)
 }
+
+// ReportError adds an error to the temporary messages, depending on
+// its severity and debug settings:
+//
+//   - If the error is nil, this never does anything.
+//   - If the error is serious, this emits the error if the debug level is
+//     -1 or greater.
+//   - If the error is only a warning, this emits the error if the debug
+//     level is 0 or greater.
+func (p *Player[C]) ReportError(e error) {
+	if e == nil || p.DebugLevel < -1 {
+		return
+	}
+	if p.DebugLevel < 0 && !IsSeriousError(e) {
+		return
+	}
+	p.ChapterBreak()
+	severity := "[Warning]"
+	if IsSeriousError(e) {
+		severity = "[ERROR]"
+	}
+	p.TemporaryMessages = append(p.TemporaryMessages, Msgf("%s: %v", severity, e))
+}
+
+// CanAct returns whether the player has actions theoretically available.
+func (p *Player[C]) CanAct() bool {
+	return p.ActionsRemaining > 0 && (len(p.Hand) > 0 || len(p.PermanentActions) > 0)
+}
diff --git a/cardsim/terminalui.go b/cardsim/terminalui.go
new file mode 100644
index 0000000..022a53f
--- /dev/null
+++ b/cardsim/terminalui.go
@@ -0,0 +1,37 @@
+package cardsim
+
+func RunSimpleTerminalUI[C StatsCollection](p *Player[C]) error {
+	for {
+		err := p.StartNextTurn()
+		if p.DebugLevel < 1 && IsSeriousError(err) {
+			return err
+		}
+		p.ReportError(err)
+
+		for p.CanAct() {
+			isCard, cardIdx, choiceIdx := pickNextAction(p)
+			var msg Message
+			if isCard {
+				msg, err = p.EnactCard(cardIdx, choiceIdx)
+			} else {
+				msg, err = p.EnactPermanentAction(cardIdx, choiceIdx)
+			}
+			p.ReportError(err)
+			if p.DebugLevel < 1 && IsSeriousError(err) {
+				return err
+			}
+			displayAndWait(msg)
+		}
+
+		review(p)
+		err = p.Simulate()
+		if p.DebugLevel < 1 && IsSeriousError(err) {
+			return err
+		}
+
+		if p.DebugLevel < 1 && p.State.Over() {
+			return nil
+		}
+	}
+	return nil
+}