diff --git a/lib/reference b/lib/reference
index 7766053..c4b6c63 160000
--- a/lib/reference
+++ b/lib/reference
@@ -1 +1 @@
-Subproject commit 7766053f9bd75bc88f43af5559747eb5b3cb6e62
+Subproject commit c4b6c63e3e9dd2604596906000d0a8bc2f8c7230
diff --git a/src/AccountV2.sol b/src/AccountV2.sol
index ffe4b09..310151d 100644
--- a/src/AccountV2.sol
+++ b/src/AccountV2.sol
@@ -11,7 +11,9 @@ import "openzeppelin-contracts/interfaces/IERC1271.sol";
 import "openzeppelin-contracts/utils/cryptography/SignatureChecker.sol";
 import "openzeppelin-contracts/proxy/utils/UUPSUpgradeable.sol";
 import "openzeppelin-contracts/access/AccessControl.sol";
-import "account-abstraction/core/BaseAccount.sol";
+
+import {BaseAccount, IEntryPoint, UserOperation, IAccount as IERC4337Account} from "account-abstraction/core/BaseAccount.sol";
+
 import "sstore2/utils/Bytecode.sol";
 
 error NotAuthorized();
@@ -37,7 +39,7 @@ contract AccountV2 is
     uint256 _nonce;
 
     // @dev address that manages upgrade and cross-chain execution settings
-    address guardian;
+    address public guardian;
 
     // @dev timestamp at which this account will be unlocked
     uint256 public lockedUntil;
@@ -75,44 +77,31 @@ contract AccountV2 is
         _;
     }
 
-    constructor(address entryPoint_) {
+    constructor(address _guardian, address entryPoint_) {
         _entryPoint = entryPoint_;
-        guardian = msg.sender;
+        guardian = _guardian;
     }
 
     receive() external payable {
-        _callOverride();
+        _handleOverride();
     }
 
-    fallback(bytes calldata)
-        external
-        payable
-        onlyUnlocked
-        returns (bytes memory)
-    {
-        return _callOverride();
+    fallback() external payable onlyUnlocked {
+        _handleOverride();
     }
 
     function executeCall(
         address to,
         uint256 value,
         bytes calldata data
-    )
-        external
-        payable
-        onlyAuthorized
-        onlyUnlocked
-        returns (bytes memory result)
-    {
+    ) external payable onlyAuthorized onlyUnlocked returns (bytes memory) {
         if (!isAuthorized(msg.sender, msg.sig)) revert NotAuthorized();
 
         ++_nonce;
 
-        result = _callOverride();
+        _handleOverride();
 
-        if (result.length != 0) {
-            result = _call(to, value, data);
-        }
+        return _call(to, value, data);
     }
 
     function setOverrides(
@@ -167,7 +156,7 @@ contract AccountV2 is
         notDelegated
         onlyGuardian
     {
-        trustedImplementations[executor] = trusted;
+        trustedExecutors[executor] = trusted;
     }
 
     function setGuardian(address _guardian) external notDelegated onlyGuardian {
@@ -183,6 +172,8 @@ contract AccountV2 is
         view
         returns (bytes4 magicValue)
     {
+        _handleOverrideStatic();
+
         bool isValid = SignatureChecker.isValidSignatureNow(
             owner(),
             hash,
@@ -206,18 +197,22 @@ contract AccountV2 is
         )
     {
         address self = address(this);
+        uint256 length = self.code.length;
+        if (length < 0x60) return (0, address(0), 0);
+
         return
             abi.decode(
-                Bytecode.codeAt(
-                    self,
-                    self.code.length - 0x60,
-                    self.code.length
-                ),
+                Bytecode.codeAt(self, length - 0x60, length),
                 (uint256, address, uint256)
             );
     }
 
-    function nonce() public view override returns (uint256) {
+    function nonce()
+        public
+        view
+        override(BaseAccount, IERC6551Account)
+        returns (uint256)
+    {
         return _nonce;
     }
 
@@ -251,7 +246,9 @@ contract AccountV2 is
         if (caller == _entryPoint) return true;
 
         // authorize trusted cross-chain executors if not on native chain
-        if (chainId != block.chainid && trustedExecutors[caller]) return true;
+        AccountV2 implementation = AccountV2(payable(_getImplementation()));
+        if (chainId != block.chainid && implementation.trustedExecutors(caller))
+            return true;
 
         // authorize caller if owner has granted permissions for function call
         if (permissions[_owner][caller][selector]) return true;
@@ -277,13 +274,14 @@ contract AccountV2 is
         bool defaultSupport = interfaceId == type(IERC165).interfaceId ||
             interfaceId == type(IERC1155Receiver).interfaceId ||
             interfaceId == type(IERC6551Account).interfaceId ||
-            interfaceId == type(IAccount).interfaceId;
+            interfaceId == type(IERC4337Account).interfaceId;
 
         if (defaultSupport) return true;
 
         // if not supported by default, check override
-        bytes memory result = _callOverrideStatic();
-        return abi.decode(result, (bool));
+        _handleOverrideStatic();
+
+        return false;
     }
 
     function onERC721Received(
@@ -292,8 +290,7 @@ contract AccountV2 is
         uint256,
         bytes memory
     ) public view override returns (bytes4) {
-        bytes memory result = _callOverrideStatic();
-        if (result.length != 0) return abi.decode(result, (bytes4));
+        _handleOverrideStatic();
 
         return this.onERC721Received.selector;
     }
@@ -305,8 +302,7 @@ contract AccountV2 is
         uint256,
         bytes memory
     ) public view override returns (bytes4) {
-        bytes memory result = _callOverrideStatic();
-        if (result.length != 0) return abi.decode(result, (bytes4));
+        _handleOverrideStatic();
 
         return this.onERC1155Received.selector;
     }
@@ -318,8 +314,7 @@ contract AccountV2 is
         uint256[] memory,
         bytes memory
     ) public view override returns (bytes4) {
-        bytes memory result = _callOverrideStatic();
-        if (result.length != 0) return abi.decode(result, (bytes4));
+        _handleOverrideStatic();
 
         return this.onERC1155BatchReceived.selector;
     }
@@ -374,11 +369,14 @@ contract AccountV2 is
         }
     }
 
-    function _callOverride() internal returns (bytes memory result) {
+    function _handleOverride() internal returns (bytes memory result) {
         address implementation = overrides[owner()][msg.sig];
 
         if (implementation != address(0)) {
             result = _call(implementation, msg.value, msg.data);
+            assembly {
+                return(add(result, 32), mload(result))
+            }
         }
     }
 
@@ -397,11 +395,18 @@ contract AccountV2 is
         }
     }
 
-    function _callOverrideStatic() internal view returns (bytes memory result) {
+    function _handleOverrideStatic()
+        internal
+        view
+        returns (bytes memory result)
+    {
         address implementation = overrides[owner()][msg.sig];
 
         if (implementation != address(0)) {
             result = _callStatic(implementation, msg.data);
+            assembly {
+                return(add(result, 32), mload(result))
+            }
         }
     }
 }
diff --git a/test/AccountV2.t.sol b/test/AccountV2.t.sol
new file mode 100644
index 0000000..4150d3c
--- /dev/null
+++ b/test/AccountV2.t.sol
@@ -0,0 +1,474 @@
+// SPDX-License-Identifier: UNLICENSED
+pragma solidity ^0.8.13;
+
+import "forge-std/Test.sol";
+
+import "openzeppelin-contracts/token/ERC20/ERC20.sol";
+import "openzeppelin-contracts/proxy/Clones.sol";
+
+import "erc6551/ERC6551Registry.sol";
+import "erc6551/interfaces/IERC6551Account.sol";
+
+import "../src/CrossChainExecutorList.sol";
+import "../src/Account.sol";
+import "../src/AccountV2.sol";
+import "../src/AccountRegistry.sol";
+
+import "./mocks/MockERC721.sol";
+import "./mocks/MockExecutor.sol";
+import "./mocks/MockReverter.sol";
+
+contract AccountV2Test is Test {
+    AccountV2 implementation;
+    ERC6551Registry public registry;
+
+    MockERC721 public tokenCollection;
+
+    function setUp() public {
+        implementation = new AccountV2(address(this), address(0));
+
+        registry = new ERC6551Registry();
+
+        tokenCollection = new MockERC721();
+    }
+
+    function testNonOwnerCallsFail(uint256 tokenId) public {
+        address user1 = vm.addr(1);
+        address user2 = vm.addr(2);
+
+        tokenCollection.mint(user1, tokenId);
+        assertEq(tokenCollection.ownerOf(tokenId), user1);
+
+        address accountAddress = registry.createAccount(
+            address(implementation),
+            block.chainid,
+            address(tokenCollection),
+            tokenId,
+            0,
+            ""
+        );
+
+        vm.deal(accountAddress, 1 ether);
+
+        AccountV2 account = AccountV2(payable(accountAddress));
+
+        // should fail if user2 tries to use account
+        vm.prank(user2);
+        vm.expectRevert(NotAuthorized.selector);
+        account.executeCall(payable(user2), 0.1 ether, "");
+
+        // should fail if user2 tries to set override
+        bytes4[] memory selectors = new bytes4[](1);
+        selectors[0] = AccountV2.executeCall.selector;
+        address[] memory implementations = new address[](1);
+        implementations[0] = vm.addr(1337);
+        vm.prank(user2);
+        vm.expectRevert(NotAuthorized.selector);
+        account.grantPermissions(selectors, implementations);
+
+        // should fail if user2 tries to lock account
+        vm.prank(user2);
+        vm.expectRevert(NotAuthorized.selector);
+        account.lock(364 days);
+    }
+
+    function testAccountOwnershipTransfer(uint256 tokenId) public {
+        address user1 = vm.addr(1);
+        address user2 = vm.addr(2);
+
+        tokenCollection.mint(user1, tokenId);
+        assertEq(tokenCollection.ownerOf(tokenId), user1);
+
+        address accountAddress = registry.createAccount(
+            address(implementation),
+            block.chainid,
+            address(tokenCollection),
+            tokenId,
+            0,
+            ""
+        );
+
+        vm.deal(accountAddress, 1 ether);
+
+        AccountV2 account = AccountV2(payable(accountAddress));
+
+        // should fail if user2 tries to use account
+        vm.prank(user2);
+        vm.expectRevert(NotAuthorized.selector);
+        account.executeCall(payable(user2), 0.1 ether, "");
+
+        vm.prank(user1);
+        tokenCollection.safeTransferFrom(user1, user2, tokenId);
+
+        // should succeed now that user2 is owner
+        vm.prank(user2);
+        account.executeCall(payable(user2), 0.1 ether, "");
+
+        assertEq(user2.balance, 0.1 ether);
+    }
+
+    function testMessageVerification(uint256 tokenId) public {
+        address user1 = vm.addr(1);
+
+        tokenCollection.mint(user1, tokenId);
+        assertEq(tokenCollection.ownerOf(tokenId), user1);
+
+        address accountAddress = registry.createAccount(
+            address(implementation),
+            block.chainid,
+            address(tokenCollection),
+            tokenId,
+            0,
+            ""
+        );
+
+        AccountV2 account = AccountV2(payable(accountAddress));
+
+        bytes32 hash = keccak256("This is a signed message");
+        (uint8 v1, bytes32 r1, bytes32 s1) = vm.sign(1, hash);
+
+        bytes memory signature1 = abi.encodePacked(r1, s1, v1);
+
+        bytes4 returnValue1 = account.isValidSignature(hash, signature1);
+
+        assertEq(returnValue1, IERC1271.isValidSignature.selector);
+    }
+
+    function testMessageVerificationForUnauthorizedUser(uint256 tokenId)
+        public
+    {
+        address user1 = vm.addr(1);
+
+        tokenCollection.mint(user1, tokenId);
+        assertEq(tokenCollection.ownerOf(tokenId), user1);
+
+        address accountAddress = registry.createAccount(
+            address(implementation),
+            block.chainid,
+            address(tokenCollection),
+            tokenId,
+            0,
+            ""
+        );
+
+        AccountV2 account = AccountV2(payable(accountAddress));
+
+        bytes32 hash = keccak256("This is a signed message");
+
+        (uint8 v2, bytes32 r2, bytes32 s2) = vm.sign(2, hash);
+        bytes memory signature2 = abi.encodePacked(r2, s2, v2);
+
+        bytes4 returnValue2 = account.isValidSignature(hash, signature2);
+
+        assertEq(returnValue2, 0);
+    }
+
+    function testAccountLocksAndUnlocks(uint256 tokenId) public {
+        address user1 = vm.addr(1);
+
+        tokenCollection.mint(user1, tokenId);
+        assertEq(tokenCollection.ownerOf(tokenId), user1);
+
+        address accountAddress = registry.createAccount(
+            address(implementation),
+            block.chainid,
+            address(tokenCollection),
+            tokenId,
+            0,
+            ""
+        );
+
+        vm.deal(accountAddress, 1 ether);
+
+        AccountV2 account = AccountV2(payable(accountAddress));
+
+        // cannot be locked for more than 365 days
+        vm.prank(user1);
+        vm.expectRevert(ExceedsMaxLockTime.selector);
+        account.lock(366 days);
+
+        // lock account for 10 days
+        uint256 unlockTimestamp = block.timestamp + 10 days;
+        vm.prank(user1);
+        account.lock(unlockTimestamp);
+
+        assertEq(account.isLocked(), true);
+
+        // transaction should revert if account is locked
+        vm.prank(user1);
+        vm.expectRevert(AccountLocked.selector);
+        account.executeCall(payable(user1), 1 ether, "");
+
+        // fallback calls should revert if account is locked
+        vm.prank(user1);
+        vm.expectRevert(AccountLocked.selector);
+        (bool success, bytes memory result) = accountAddress.call(
+            abi.encodeWithSignature("customFunction()")
+        );
+
+        // silence unused variable compiler warnings
+        success;
+        result;
+
+        // setOverrides calls should revert if account is locked
+        {
+            bytes4[] memory selectors = new bytes4[](1);
+            selectors[0] = AccountV2.executeCall.selector;
+            address[] memory implementations = new address[](1);
+            implementations[0] = vm.addr(1337);
+            vm.prank(user1);
+            vm.expectRevert(AccountLocked.selector);
+            account.setOverrides(selectors, implementations);
+        }
+
+        // lock calls should revert if account is locked
+        vm.prank(user1);
+        vm.expectRevert(Account.AccountLocked.selector);
+        account.lock(0);
+
+        // signing should fail if account is locked
+        bytes32 hash = keccak256("This is a signed message");
+        (uint8 v1, bytes32 r1, bytes32 s1) = vm.sign(2, hash);
+        bytes memory signature1 = abi.encodePacked(r1, s1, v1);
+        bytes4 returnValue = account.isValidSignature(hash, signature1);
+        assertEq(returnValue, 0);
+
+        // warp to timestamp after account is unlocked
+        vm.warp(unlockTimestamp + 1 days);
+
+        // transaction succeed now that account lock has expired
+        vm.prank(user1);
+        account.executeCall(payable(user1), 1 ether, "");
+        assertEq(user1.balance, 1 ether);
+
+        // signing should now that account lock has expired
+        bytes32 hashAfterUnlock = keccak256("This is a signed message");
+        (uint8 v2, bytes32 r2, bytes32 s2) = vm.sign(1, hashAfterUnlock);
+        bytes memory signature2 = abi.encodePacked(r2, s2, v2);
+        bytes4 returnValue1 = account.isValidSignature(
+            hashAfterUnlock,
+            signature2
+        );
+        assertEq(returnValue1, IERC1271.isValidSignature.selector);
+    }
+
+    function testCustomOverridesFallback(uint256 tokenId) public {
+        address user1 = vm.addr(1);
+
+        tokenCollection.mint(user1, tokenId);
+        assertEq(tokenCollection.ownerOf(tokenId), user1);
+
+        address accountAddress = registry.createAccount(
+            address(implementation),
+            block.chainid,
+            address(tokenCollection),
+            tokenId,
+            0,
+            ""
+        );
+
+        vm.deal(accountAddress, 1 ether);
+
+        AccountV2 account = AccountV2(payable(accountAddress));
+
+        MockExecutor mockExecutor = new MockExecutor();
+
+        // calls succeed with noop if override is undefined
+        (bool success, bytes memory result) = accountAddress.call(
+            abi.encodeWithSignature("customFunction()")
+        );
+        assertEq(success, true);
+        assertEq(result, "");
+
+        // set overrides on account
+        bytes4[] memory selectors = new bytes4[](2);
+        selectors[0] = bytes4(abi.encodeWithSignature("customFunction()"));
+        selectors[1] = bytes4(abi.encodeWithSignature("fail()"));
+        address[] memory implementations = new address[](2);
+        implementations[0] = address(mockExecutor);
+        implementations[1] = address(mockExecutor);
+        vm.prank(user1);
+        account.setOverrides(selectors, implementations);
+
+        // execution module handles fallback calls
+        assertEq(MockExecutor(accountAddress).customFunction(), 12345);
+
+        // execution bubbles up errors on revert
+        vm.expectRevert(MockReverter.MockError.selector);
+        MockExecutor(accountAddress).fail();
+    }
+
+    /**/
+    function testCustomPermissions(uint256 tokenId) public {
+        address user1 = vm.addr(1);
+        address user2 = vm.addr(2);
+
+        tokenCollection.mint(user1, tokenId);
+        assertEq(tokenCollection.ownerOf(tokenId), user1);
+
+        address accountAddress = registry.createAccount(
+            address(implementation),
+            block.chainid,
+            address(tokenCollection),
+            tokenId,
+            0,
+            ""
+        );
+
+        vm.deal(accountAddress, 1 ether);
+
+        AccountV2 account = AccountV2(payable(accountAddress));
+
+        bytes4 selector = bytes4(
+            abi.encodeWithSignature("executeCall(address,uint256,bytes)")
+        );
+
+        assertEq(account.isAuthorized(user2, selector), false);
+
+        bytes4[] memory selectors = new bytes4[](1);
+        selectors[0] = selector;
+        address[] memory implementations = new address[](1);
+        implementations[0] = address(user2);
+        vm.prank(user1);
+        account.grantPermissions(selectors, implementations);
+
+        assertEq(account.isAuthorized(user2, selector), true);
+
+        vm.prank(user2);
+        account.executeCall(user2, 0.1 ether, "");
+
+        assertEq(user2.balance, 0.1 ether);
+    }
+
+    function testCrossChainCalls() public {
+        uint256 tokenId = 1;
+        address user1 = vm.addr(1);
+        address crossChainExecutor = vm.addr(2);
+
+        uint256 chainId = block.chainid + 1;
+
+        tokenCollection.mint(user1, tokenId);
+        assertEq(tokenCollection.ownerOf(tokenId), user1);
+
+        address accountAddress = registry.createAccount(
+            address(implementation),
+            chainId,
+            address(tokenCollection),
+            tokenId,
+            0,
+            ""
+        );
+
+        vm.deal(accountAddress, 1 ether);
+
+        AccountV2 account = AccountV2(payable(accountAddress));
+
+        bytes4 selector = bytes4(
+            abi.encodeWithSignature("executeCall(address,uint256,bytes)")
+        );
+
+        assertEq(account.isAuthorized(crossChainExecutor, selector), false);
+
+        implementation.setTrustedExecutor(crossChainExecutor, true);
+
+        assertEq(account.isAuthorized(crossChainExecutor, selector), true);
+
+        vm.prank(crossChainExecutor);
+        account.executeCall(user1, 0.1 ether, "");
+
+        assertEq(user1.balance, 0.1 ether);
+
+        address notCrossChainExecutor = vm.addr(3);
+        vm.prank(notCrossChainExecutor);
+        vm.expectRevert(NotAuthorized.selector);
+        AccountV2(payable(account)).executeCall(user1, 0.1 ether, "");
+
+        assertEq(user1.balance, 0.1 ether);
+
+        address nativeAccountAddress = registry.createAccount(
+            address(implementation),
+            block.chainid,
+            address(tokenCollection),
+            tokenId,
+            0,
+            ""
+        );
+
+        vm.prank(crossChainExecutor);
+        vm.expectRevert(NotAuthorized.selector);
+        AccountV2(payable(nativeAccountAddress)).executeCall(
+            user1,
+            0.1 ether,
+            ""
+        );
+
+        assertEq(user1.balance, 0.1 ether);
+    }
+
+    function testExecuteCallRevert(uint256 tokenId) public {
+        address user1 = vm.addr(1);
+
+        tokenCollection.mint(user1, tokenId);
+        assertEq(tokenCollection.ownerOf(tokenId), user1);
+
+        address accountAddress = registry.createAccount(
+            address(implementation),
+            block.chainid,
+            address(tokenCollection),
+            tokenId,
+            0,
+            ""
+        );
+
+        vm.deal(accountAddress, 1 ether);
+
+        AccountV2 account = AccountV2(payable(accountAddress));
+
+        MockReverter mockReverter = new MockReverter();
+
+        vm.prank(user1);
+        vm.expectRevert(MockReverter.MockError.selector);
+        account.executeCall(
+            payable(address(mockReverter)),
+            0,
+            abi.encodeWithSignature("fail()")
+        );
+    }
+
+    function testAccountOwnerIsNullIfContextNotSet() public {
+        address accountClone = Clones.clone(address(implementation));
+
+        assertEq(AccountV2(payable(accountClone)).owner(), address(0));
+    }
+
+    function testEIP165Support() public {
+        uint256 tokenId = 1;
+        address user1 = vm.addr(1);
+
+        tokenCollection.mint(user1, tokenId);
+        assertEq(tokenCollection.ownerOf(tokenId), user1);
+
+        address accountAddress = registry.createAccount(
+            address(implementation),
+            block.chainid,
+            address(tokenCollection),
+            tokenId,
+            0,
+            ""
+        );
+
+        vm.deal(accountAddress, 1 ether);
+
+        AccountV2 account = AccountV2(payable(accountAddress));
+
+        assertEq(
+            account.supportsInterface(type(IERC6551Account).interfaceId),
+            true
+        );
+        assertEq(
+            account.supportsInterface(type(IERC1155Receiver).interfaceId),
+            true
+        );
+        assertEq(account.supportsInterface(type(IERC165).interfaceId), true);
+    }
+}