Ouptut 0 disassembles as:
OP_IF OP_INVALIDOPCODE 4effffffff <large constant> OP_ENDIF
The large constant contains an ASCII Bitcoin Core patch entitled Remove (SINGLE|DOUBLE)BYTE so presumably this is a proof of concept:
From a3a61fef43309b9fb23225df7910b03afc5465b9 Mon Sep 17 00:00:00 2001
From: Satoshi Nakamoto <satoshin@gmx.com>
Date: Mon, 12 Aug 2013 02:28:02 -0200
Subject: [PATCH] Remove (SINGLE|DOUBLE)BYTE

I removed this from Bitcoin in f1e1fb4bdef878c8fc1564fa418d44e7541a7e83
in Sept 7 2010, almost three years ago. Be warned that I have not
actually tested this patch.
---
 backends/bitcoind/deserialize.py |    8 +-------
 1 file changed, 1 insertion(+), 7 deletions(-)

diff --git a/backends/bitcoind/deserialize.py b/backends/bitcoind/deserialize.py
index 6620583..89b9b1b 100644
--- a/backends/bitcoind/deserialize.py
+++ b/backends/bitcoind/deserialize.py
@@ -280,10 +280,8 @@ opcodes = Enumeration("Opcodes", [
     "OP_WITHIN", "OP_RIPEMD160", "OP_SHA1", "OP_SHA256", "OP_HASH160",
     "OP_HASH256", "OP_CODESEPARATOR", "OP_CHECKSIG", "OP_CHECKSIGVERIFY", "OP_CHECKMULTISIG",
     "OP_CHECKMULTISIGVERIFY",
-    ("OP_SINGLEBYTE_END", 0xF0),
-    ("OP_DOUBLEBYTE_BEGIN", 0xF000),
     "OP_PUBKEY", "OP_PUBKEYHASH",
-    ("OP_INVALIDOPCODE", 0xFFFF),
+    ("OP_INVALIDOPCODE", 0xFF),
 ])
 
 
@@ -293,10 +291,6 @@ def script_GetOp(bytes):
         vch = None
         opcode = ord(bytes[i])
         i += 1
-        if opcode >= opcodes.OP_SINGLEBYTE_END and i < len(bytes):
-            opcode <<= 8
-            opcode |= ord(bytes[i])
-            i += 1
 
         if opcode <= opcodes.OP_PUSHDATA4:
             nSize = opcode
-- 
1.7.9.4
bitcointalk.org/index.php?topic=5231222.0 duscusses what happens if there is an invalid opcode in a branch that is not taken.