diff --git a/packages/arena/src/index.ts b/packages/arena/src/index.ts
index 026890c..3420d7b 100644
--- a/packages/arena/src/index.ts
+++ b/packages/arena/src/index.ts
@@ -28,6 +28,9 @@ export function apply(ctx: Context, config: Config) {
       ctx.logger.debug(elemnts)
       ctx.logger.debug(prefix)
 
+      if (!elemnts || !elemnts.length) {
+        return next()
+      }
       if (elemnts[0].type === 'at' && elemnts[0].attrs?.id === selfId) {
         elemnts.shift()
       }