diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index aa3cb5f..d3c6e04 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -68,9 +68,11 @@ jobs:
           python3 - <<'EOF'
           import json, sys
           from pathlib import Path
-          # The instance-based cases (01-04, 06) fail on a fresh emulator
-          # because no AMI is seeded (see PR #43); add them once that lands.
-          REQUIRED = {"00-simple-vpc", "05-vpc-with-subnet"}
+          REQUIRED = {
+              "00-simple-vpc", "01-hello-world", "02-one-server",
+              "03-one-webserver", "04-one-webserver-with-vars",
+              "05-vpc-with-subnet", "06-instance-in-vpc",
+          }
           runs = sorted(p for p in Path('tests/tf/runs').iterdir() if p.is_dir())
           summary = runs[-1] / 'summary.json' if runs else None
           if not summary or not summary.exists():
diff --git a/emulators/aws-ec2/emulator_core/services/ami.py b/emulators/aws-ec2/emulator_core/services/ami.py
index 2a68f58..cde59c0 100644
--- a/emulators/aws-ec2/emulator_core/services/ami.py
+++ b/emulators/aws-ec2/emulator_core/services/ami.py
@@ -151,6 +151,47 @@ class Ami_Backend:
     def __init__(self):
         self.state = EC2State.get()
         self.resources = self.state.amis  # alias to shared store
+        self._ensure_default_images()
+
+    def _ensure_default_images(self) -> None:
+        if self.resources:
+            return
+
+        amazon_linux_2 = Ami(
+            image_id="ami-0f9fc25dd2506cf6d",
+            owner_id="137112412989",
+            image_owner_id="137112412989",
+            image_owner_alias="amazon",
+            name="amzn2-ami-hvm-2.0.20240109.0-x86_64-gp2",
+            description="Amazon Linux 2 AMI (HVM), SSD Volume Type",
+            state="available",
+            image_state="available",
+            image_type="machine",
+            architecture="x86_64",
+            creation_date="2024-01-09T00:00:00.000Z",
+            is_public=True,
+            image_location="amazon/amzn2-ami-hvm-2.0.20240109.0-x86_64-gp2",
+            platform_details="Linux/UNIX",
+            root_device_name="/dev/xvda",
+            root_device_type="ebs",
+            virtualization_type="hvm",
+            ena_support=True,
+            sriov_net_support="simple",
+            hypervisor="xen",
+            block_device_mappings=[
+                {
+                    "deviceName": "/dev/xvda",
+                    "ebs": {
+                        "deleteOnTermination": True,
+                        "encrypted": False,
+                        "snapshotId": "snap-0f9fc25dd2506cf6d",
+                        "volumeSize": 8,
+                        "volumeType": "gp2",
+                    },
+                }
+            ],
+        )
+        self.resources[amazon_linux_2.image_id] = amazon_linux_2
 
     def _utc_now(self) -> str:
         return datetime.now(timezone.utc).strftime("%Y-%m-%dT%H:%M:%SZ")
@@ -635,7 +676,13 @@ def DescribeImages(self, params: Dict[str, Any]):
 
         owners = params.get("Owner.N", []) or []
         if owners:
-            resources = [image for image in resources if image.owner_id in owners or image.image_owner_id in owners]
+            resources = [
+                image
+                for image in resources
+                if image.owner_id in owners
+                or image.image_owner_id in owners
+                or image.image_owner_alias in owners
+            ]
 
         include_disabled = str2bool(params.get("IncludeDisabled"))
         include_deprecated = str2bool(params.get("IncludeDeprecated"))
@@ -3111,4 +3158,3 @@ def serialize(action: str, data: Dict[str, Any], request_id: str) -> str:
         if action not in serializers:
             raise ValueError(f"Unknown action: {action}")
         return serializers[action](data, request_id)
-
diff --git a/emulators/aws-ec2/emulator_core/services/dhcpoptions.py b/emulators/aws-ec2/emulator_core/services/dhcpoptions.py
index 6552d88..0ebd021 100644
--- a/emulators/aws-ec2/emulator_core/services/dhcpoptions.py
+++ b/emulators/aws-ec2/emulator_core/services/dhcpoptions.py
@@ -118,7 +118,7 @@ def CreateDhcpOptions(self, params: Dict[str, Any]):
                 "Missing required parameter: DhcpConfiguration.N",
             )
 
-        dhcp_options_id = self._generate_id("dhcp")
+        dhcp_options_id = self._generate_id("dopt")
         tag_set: List[Dict[str, Any]] = []
         for spec in params.get("TagSpecification.N", []) or []:
             tag_set.extend(spec.get("Tags", []) or [])
@@ -132,7 +132,7 @@ def CreateDhcpOptions(self, params: Dict[str, Any]):
         self.resources[dhcp_options_id] = resource
 
         return {
-            'dhcpOptions': [resource.to_dict()],
+            'dhcpOptions': resource.to_dict(),
             }
 
     def DeleteDhcpOptions(self, params: Dict[str, Any]):
@@ -211,8 +211,23 @@ def parse_associate_dhcp_options_request(md: Dict[str, Any]) -> Dict[str, Any]:
 
     @staticmethod
     def parse_create_dhcp_options_request(md: Dict[str, Any]) -> Dict[str, Any]:
+        def parse_dhcp_configurations() -> List[Dict[str, Any]]:
+            configurations: List[Dict[str, Any]] = []
+            index = 1
+            while True:
+                key = get_scalar(md, f"DhcpConfiguration.{index}.Key")
+                if key is None:
+                    break
+                values = get_indexed_list(md, f"DhcpConfiguration.{index}.Value")
+                configurations.append({
+                    "key": key,
+                    "valueSet": [{"value": value} for value in values],
+                })
+                index += 1
+            return configurations
+
         return {
-            "DhcpConfiguration.N": get_indexed_list(md, "DhcpConfiguration"),
+            "DhcpConfiguration.N": parse_dhcp_configurations(),
             "DryRun": str2bool(get_scalar(md, "DryRun")),
             "TagSpecification.N": parse_tags(md, "TagSpecification"),
         }
@@ -345,15 +360,9 @@ def serialize_create_dhcp_options_response(data: Dict[str, Any], request_id: str
         if _dhcpOptions_key:
             param_data = data[_dhcpOptions_key]
             indent_str = "    " * 1
-            if param_data:
-                xml_parts.append(f'{indent_str}<dhcpOptionsSet>')
-                for item in param_data:
-                    xml_parts.append(f'{indent_str}    <item>')
-                    xml_parts.extend(dhcpoptions_ResponseSerializer._serialize_nested_fields(item, 2))
-                    xml_parts.append(f'{indent_str}    </item>')
-                xml_parts.append(f'{indent_str}</dhcpOptionsSet>')
-            else:
-                xml_parts.append(f'{indent_str}<dhcpOptionsSet/>')
+            xml_parts.append(f'{indent_str}<dhcpOptions>')
+            xml_parts.extend(dhcpoptions_ResponseSerializer._serialize_nested_fields(param_data, 2))
+            xml_parts.append(f'{indent_str}</dhcpOptions>')
         xml_parts.append(f'</CreateDhcpOptionsResponse>')
         return "\n".join(xml_parts)
 
@@ -428,4 +437,3 @@ def serialize(action: str, data: Dict[str, Any], request_id: str) -> str:
         if action not in serializers:
             raise ValueError(f"Unknown action: {action}")
         return serializers[action](data, request_id)
-
diff --git a/emulators/aws-ec2/emulator_core/services/internetgateway.py b/emulators/aws-ec2/emulator_core/services/internetgateway.py
index 4aeb81a..51f1ca0 100644
--- a/emulators/aws-ec2/emulator_core/services/internetgateway.py
+++ b/emulators/aws-ec2/emulator_core/services/internetgateway.py
@@ -395,7 +395,7 @@ def DetachInternetGateway(self, params: Dict[str, Any]):
             )
 
         resource.vpc_id = None
-        resource.attachment_set = [{"state": "detached", "vpcId": vpc_id}]
+        resource.attachment_set = []
 
         if hasattr(vpc, "internet_gateway_ids") and internet_gateway_id in vpc.internet_gateway_ids:
             vpc.internet_gateway_ids.remove(internet_gateway_id)
@@ -778,4 +778,3 @@ def serialize(action: str, data: Dict[str, Any], request_id: str) -> str:
         if action not in serializers:
             raise ValueError(f"Unknown action: {action}")
         return serializers[action](data, request_id)
-
diff --git a/emulators/aws-ec2/emulator_core/services/vpc.py b/emulators/aws-ec2/emulator_core/services/vpc.py
index 0bb656c..6aeea9c 100644
--- a/emulators/aws-ec2/emulator_core/services/vpc.py
+++ b/emulators/aws-ec2/emulator_core/services/vpc.py
@@ -426,7 +426,32 @@ def DescribeVpcs(self, params: Dict[str, Any]):
         else:
             resources = list(self.resources.values())
 
-        resources = apply_filters(resources, params.get("Filter.N", []))
+        filters = params.get("Filter.N", []) or []
+        special_filter_names = {
+            "cidr-block-association.association-id",
+            "ipv6-cidr-block-association.association-id",
+        }
+        for resource_filter in filters:
+            name = resource_filter.get("Name", "")
+            values = set(resource_filter.get("Values", []) or [])
+            if name not in special_filter_names or not values:
+                continue
+            association_attr = (
+                "ipv6_cidr_block_association_set"
+                if name.startswith("ipv6-")
+                else "cidr_block_association_set"
+            )
+            resources = [
+                resource
+                for resource in resources
+                if any(
+                    str(association.get("associationId", "")) in values
+                    for association in getattr(resource, association_attr, []) or []
+                    if isinstance(association, dict)
+                )
+            ]
+        normal_filters = [f for f in filters if f.get("Name", "") not in special_filter_names]
+        resources = apply_filters(resources, normal_filters)
         vpc_set = [resource.to_dict() for resource in resources[:max_results]]
 
         return {
diff --git a/emulators/aws-ec2/emulator_core/services/vpcpeering.py b/emulators/aws-ec2/emulator_core/services/vpcpeering.py
index d6ecc6d..c008360 100644
--- a/emulators/aws-ec2/emulator_core/services/vpcpeering.py
+++ b/emulators/aws-ec2/emulator_core/services/vpcpeering.py
@@ -1,5 +1,5 @@
 from typing import Dict, List, Any, Optional
-from datetime import datetime, timezone
+from datetime import datetime, timezone, timedelta
 from dataclasses import dataclass, field, asdict
 from enum import Enum
 import uuid
@@ -189,7 +189,7 @@ def _build_vpc_info(vpc_obj, owner_override: Optional[str], region_override: Opt
 
         resource = VpcPeering(
             accepter_vpc_info=accepter_info,
-            expiration_time="",
+            expiration_time=(datetime.now(timezone.utc) + timedelta(days=7)).isoformat().replace("+00:00", "Z"),
             requester_vpc_info=requester_info,
             status=status,
             tag_set=tag_set,
@@ -661,4 +661,3 @@ def serialize(action: str, data: Dict[str, Any], request_id: str) -> str:
         if action not in serializers:
             raise ValueError(f"Unknown action: {action}")
         return serializers[action](data, request_id)
-
diff --git a/emulators/aws-ec2/emulator_core/utils.py b/emulators/aws-ec2/emulator_core/utils.py
index 1f4b901..b850803 100644
--- a/emulators/aws-ec2/emulator_core/utils.py
+++ b/emulators/aws-ec2/emulator_core/utils.py
@@ -1,6 +1,7 @@
 from typing import Dict, Any, List, Union, Optional
 from werkzeug.datastructures import MultiDict
 import html
+import fnmatch
 
 # ==================== TYPE ALIASES ====================
 # These help clarify what types functions return
@@ -376,6 +377,13 @@ def serialize_error_response(error_data: ErrorResponse, request_id: str) -> str:
 </Response>"""
 
 
+def _matches_filter_value(actual: str, expected_values: List[str]) -> bool:
+    for expected in expected_values:
+        if fnmatch.fnmatchcase(actual, str(expected)):
+            return True
+    return False
+
+
 def apply_filters(resources: List[Any], filters: List[Filter]) -> List[Any]:
     """
     Apply AWS-style filters to a list of resource objects or dicts.
@@ -425,7 +433,7 @@ def apply_filters(resources: List[Any], filters: List[Filter]) -> List[Any]:
                     if isinstance(tag, dict) and tag.get("Key") == tag_key:
                         tag_value = tag.get("Value", "")
                         break
-                if tag_value is None or tag_value not in values:
+                if tag_value is None or not _matches_filter_value(str(tag_value), values):
                     match = False
                     break
                 continue
@@ -452,14 +460,14 @@ def apply_filters(resources: List[Any], filters: List[Filter]) -> List[Any]:
             elif isinstance(obj, list):
                 # List field: pass if any element matches any value
                 list_strs = [str(item) for item in obj]
-                if not any(v in list_strs for v in values):
+                if not any(_matches_filter_value(item, values) for item in list_strs):
                     match = False
                     break
                 continue
             else:
                 val_str = str(obj)
 
-            if val_str not in values:
+            if not _matches_filter_value(val_str, values):
                 match = False
                 break
 
diff --git a/emulators/aws-ec2/tests/tf/01-hello-world/main.tf b/emulators/aws-ec2/tests/tf/01-hello-world/main.tf
index c788f67..da8f41e 100644
--- a/emulators/aws-ec2/tests/tf/01-hello-world/main.tf
+++ b/emulators/aws-ec2/tests/tf/01-hello-world/main.tf
@@ -5,6 +5,6 @@ provider "aws" {
 
 # Create an EC2 instance
 resource "aws_instance" "example" {
-  ami           = "ami-13095cba0d3649579"
+  ami           = "ami-0f9fc25dd2506cf6d"
   instance_type = "t2.micro"
 }
\ No newline at end of file
diff --git a/emulators/aws-ec2/tests/tf/02-one-server/main.tf b/emulators/aws-ec2/tests/tf/02-one-server/main.tf
index 5458f44..b6a3b16 100644
--- a/emulators/aws-ec2/tests/tf/02-one-server/main.tf
+++ b/emulators/aws-ec2/tests/tf/02-one-server/main.tf
@@ -5,7 +5,7 @@ provider "aws" {
 
 # Create an EC2 instance
 resource "aws_instance" "example" {
-  ami           = "ami-13095cba0d3649579"
+  ami           = "ami-0f9fc25dd2506cf6d"
   instance_type = "t2.micro"
   
   tags = {
diff --git a/emulators/aws-ec2/tests/tf/03-one-webserver/main.tf b/emulators/aws-ec2/tests/tf/03-one-webserver/main.tf
index f47088e..725ae45 100644
--- a/emulators/aws-ec2/tests/tf/03-one-webserver/main.tf
+++ b/emulators/aws-ec2/tests/tf/03-one-webserver/main.tf
@@ -17,7 +17,7 @@ resource "aws_security_group" "instance" {
 
 # Create an EC2 instance
 resource "aws_instance" "example" {
-  ami                     = "ami-13095cba0d3649579"
+  ami                     = "ami-0f9fc25dd2506cf6d"
   instance_type           = "t2.micro"
   vpc_security_group_ids  = ["${aws_security_group.instance.id}"]
   
diff --git a/emulators/aws-ec2/tests/tf/04-one-webserver-with-vars/main.tf b/emulators/aws-ec2/tests/tf/04-one-webserver-with-vars/main.tf
index bb631ab..74ca21e 100644
--- a/emulators/aws-ec2/tests/tf/04-one-webserver-with-vars/main.tf
+++ b/emulators/aws-ec2/tests/tf/04-one-webserver-with-vars/main.tf
@@ -17,7 +17,7 @@ resource "aws_security_group" "instance" {
 
 # Create an EC2 instance
 resource "aws_instance" "example" {
-  ami			                = "ami-13095cba0d3649579"
+  ami			                = "ami-0f9fc25dd2506cf6d"
   instance_type           = "t2.micro"
   vpc_security_group_ids  = ["${aws_security_group.instance.id}"]
   
diff --git a/emulators/aws-ec2/tests/tf/06-instance-in-vpc/main.tf b/emulators/aws-ec2/tests/tf/06-instance-in-vpc/main.tf
index 3f7156e..6f48d85 100644
--- a/emulators/aws-ec2/tests/tf/06-instance-in-vpc/main.tf
+++ b/emulators/aws-ec2/tests/tf/06-instance-in-vpc/main.tf
@@ -48,7 +48,7 @@ resource "aws_security_group" "instance" {
 
 # EC2 instance in VPC
 resource "aws_instance" "example" {
-  ami                    = "ami-13095cba0d3649579"
+  ami                    = "ami-0f9fc25dd2506cf6d"
   instance_type          = "t2.micro"
   subnet_id              = "${aws_subnet.main.id}"
   vpc_security_group_ids = ["${aws_security_group.instance.id}"]