diff --git a/Makefile b/Makefile
index 2bb3506b..385b872a 100644
--- a/Makefile
+++ b/Makefile
@@ -11,7 +11,7 @@ DOCKER_ORG          ?= avaplatform
 DOCKER_IMAGE        ?= ${DOCKER_ORG}/${PROJECT}
 DOCKER_LABEL        ?= latest
 DOCKER_TAG          ?= ${DOCKER_IMAGE}:${DOCKER_LABEL}
-AVALANCHE_VERSION   ?= v1.6.5
+AVALANCHE_VERSION   ?= v1.7.0
 
 build:
 	go build -o ./rosetta-server ./cmd/server
diff --git a/cmd/server/main.go b/cmd/server/main.go
index 498cda21..808071ca 100644
--- a/cmd/server/main.go
+++ b/cmd/server/main.go
@@ -74,11 +74,14 @@ func main() {
 	}
 
 	var assetID string
+	var AP5Activation uint64
 	switch cfg.ChainID {
 	case mapper.MainnetChainID:
 		assetID = mapper.MainnetAssetID
+		AP5Activation = mapper.MainnetAP5Activation.Uint64()
 	case mapper.FujiChainID:
 		assetID = mapper.FujiAssetID
+		AP5Activation = mapper.FujiAP5Activation.Uint64()
 	default:
 		log.Fatal("invalid ChainID:", cfg.ChainID)
 	}
@@ -119,6 +122,7 @@ func main() {
 		NetworkID:        network,
 		GenesisBlockHash: cfg.GenesisBlockHash,
 		AvaxAssetID:      assetID,
+		AP5Activation:    AP5Activation,
 	}
 
 	handler := configureRouter(serviceConfig, asserter, apiClient)
diff --git a/go.mod b/go.mod
index 95eaee05..ff88f546 100644
--- a/go.mod
+++ b/go.mod
@@ -4,8 +4,8 @@ go 1.16
 
 require (
 	github.com/StackExchange/wmi v0.0.0-20190523213315-cbe66965904d // indirect
-	github.com/ava-labs/avalanchego v1.6.5
-	github.com/ava-labs/coreth v0.7.4-rc.1
+	github.com/ava-labs/avalanchego v1.7.0
+	github.com/ava-labs/coreth v0.8.0-rc.3
 	github.com/coinbase/rosetta-sdk-go v0.6.5
 	github.com/decred/dcrd/dcrec/secp256k1/v3 v3.0.0 // indirect
 	github.com/ethereum/go-ethereum v1.10.12
diff --git a/go.sum b/go.sum
index aec077c1..65f2e791 100644
--- a/go.sum
+++ b/go.sum
@@ -42,7 +42,6 @@ github.com/DataDog/zstd v1.4.1/go.mod h1:1jcaCB/ufaK+sKp1NBhlGmpz41jOoPQ35bpF36t
 github.com/DataDog/zstd v1.4.5/go.mod h1:1jcaCB/ufaK+sKp1NBhlGmpz41jOoPQ35bpF36t7BBo=
 github.com/Knetic/govaluate v3.0.1-0.20171022003610-9aa49832a739+incompatible/go.mod h1:r7JcOSlj0wfOMncg0iLm8Leh48TZaKVeNIfJntJ2wa0=
 github.com/Microsoft/go-winio v0.4.14/go.mod h1:qXqCSQ3Xa7+6tgxaGTIe4Kpcdsi+P8jBhyzoq1bpyYA=
-github.com/NYTimes/gziphandler v1.1.1 h1:ZUDjpQae29j0ryrS0u/B8HZfJBtBQHjqw2rQ2cqUQ3I=
 github.com/NYTimes/gziphandler v1.1.1/go.mod h1:n/CVRwUEOgIxrgPvAQhUUr9oeUtvrhMomdKFjzJNB0c=
 github.com/OneOfOne/xxhash v1.2.2/go.mod h1:HSdplMjZKSmBqAxg5vPj2TmRDmfkzw+cTzAElWljhcU=
 github.com/Shopify/sarama v1.19.0/go.mod h1:FVkBWblsNy7DGZRfXLU0O9RCGt5g3g3yEuWXgklEdEo=
@@ -75,11 +74,11 @@ github.com/armon/consul-api v0.0.0-20180202201655-eb2c6b5be1b6/go.mod h1:grANhF5
 github.com/armon/go-metrics v0.0.0-20180917152333-f0300d1749da/go.mod h1:Q73ZrmVTwzkszR9V5SSuryQ31EELlFMUz1kKyl939pY=
 github.com/armon/go-radix v0.0.0-20180808171621-7fddfc383310/go.mod h1:ufUuZ+zHj4x4TnLV4JWEpy2hxWSpsRywHrMgIH9cCH8=
 github.com/aryann/difflib v0.0.0-20170710044230-e206f873d14a/go.mod h1:DAHtR1m6lCRdSC2Tm3DSWRPvIPr6xNKyeHdqDQSQT+A=
-github.com/ava-labs/avalanchego v1.6.4/go.mod h1:DzxlGkF8hj3GiwRoQfHq9gJfyt4EyeIpAsdfBOBg6mI=
-github.com/ava-labs/avalanchego v1.6.5 h1:xzta2OGAjF7ka06Cl1IoB4jtrqhAuxjI1onVDGWwdsk=
-github.com/ava-labs/avalanchego v1.6.5/go.mod h1:M21LNXMX5AcvUfQ0x1wKewOEgJjOcq8W08m3gmnGJAU=
-github.com/ava-labs/coreth v0.7.4-rc.1 h1:d2UAV+f1Ku3Ngu//tctGH5c45g38sZh1Re47QNW/Xi8=
-github.com/ava-labs/coreth v0.7.4-rc.1/go.mod h1:Tfx58OW7evspvjd69fM/cQ9UyPtYGTfUkGBsP5PtAK8=
+github.com/ava-labs/avalanchego v1.6.6-0.20211122023205-994831adda9b/go.mod h1:jwfTpP+SB9AZVnHBuh3/d2WNbsIgGwUpqOfOgtEkelk=
+github.com/ava-labs/avalanchego v1.7.0 h1:u9QuyXy1vYrUDqPrYD5+2Q5/OzUQMRIgcAq8Tuo02dA=
+github.com/ava-labs/avalanchego v1.7.0/go.mod h1:jwfTpP+SB9AZVnHBuh3/d2WNbsIgGwUpqOfOgtEkelk=
+github.com/ava-labs/coreth v0.8.0-rc.3 h1:5RLBY11Om1PEUQ71wtf+Qtut2uZRuj8+sIpB0Q/SfvE=
+github.com/ava-labs/coreth v0.8.0-rc.3/go.mod h1:rxTZLwjo6dfyPRkf5WfLEFP3C6Tn21lCjjLUH5XqeqM=
 github.com/aws/aws-lambda-go v1.13.3/go.mod h1:4UKl9IzQMoD+QF79YdCuzCwp8VbmG4VAQwij/eHl5CU=
 github.com/aws/aws-sdk-go v1.25.48/go.mod h1:KmX6BPdI08NWTb3/sm4ZGu5ShLoqVDhKgpiN924inxo=
 github.com/aws/aws-sdk-go v1.27.0/go.mod h1:KmX6BPdI08NWTb3/sm4ZGu5ShLoqVDhKgpiN924inxo=
@@ -327,7 +326,6 @@ github.com/googleapis/gax-go/v2 v2.0.4/go.mod h1:0Wqv26UfaUD9n4G6kQubkQ+KchISgw+
 github.com/googleapis/gax-go/v2 v2.0.5/go.mod h1:DWXyrwAJ9X0FpwwEdw+IPEYBICEFu5mhpdKc/us6bOk=
 github.com/gopherjs/gopherjs v0.0.0-20181017120253-0766667cb4d1/go.mod h1:wJfORRmW1u3UXTncJ5qlYoELFm8eSnnEO6hX4iZ3EWY=
 github.com/gorilla/context v1.1.1/go.mod h1:kBGZzfjB9CEq2AlWe17Uuf7NDRt0dE0s8S51q0aT7Yg=
-github.com/gorilla/handlers v1.4.2 h1:0QniY0USkHQ1RGCLfKxeNHK9bkDHGRYGNDFBCS+YARg=
 github.com/gorilla/handlers v1.4.2/go.mod h1:Qkdc/uu4tH4g6mTK6auzZ766c4CA0Ng8+o/OAirnOIQ=
 github.com/gorilla/mux v1.6.2/go.mod h1:1lud6UwP+6orDFRuTfBEV8e9/aOM/c4fVVCaMa2zaAs=
 github.com/gorilla/mux v1.7.3/go.mod h1:1lud6UwP+6orDFRuTfBEV8e9/aOM/c4fVVCaMa2zaAs=
@@ -632,7 +630,6 @@ github.com/rjeczalik/notify v0.9.2/go.mod h1:aErll2f0sUX9PXZnVNyeiObbmTlk5jnMoCa
 github.com/rogpeppe/fastuuid v0.0.0-20150106093220-6724a57986af/go.mod h1:XWv6SoW27p1b0cqNHllgS5HIMJraePCO15w5zCzIWYg=
 github.com/rogpeppe/go-internal v1.3.0/go.mod h1:M8bDsm7K2OlrFYOpmOWEs/qY81heoFRclV5y23lUDJ4=
 github.com/rs/cors v0.0.0-20160617231935-a62a804a8a00/go.mod h1:gFx+x8UowdsKA9AchylcLynDq+nNFfI8FkUZdN/jGCU=
-github.com/rs/cors v1.7.0 h1:+88SsELBHx5r+hZ8TCkggzSstaWNbDvThkVK8H6f9ik=
 github.com/rs/cors v1.7.0/go.mod h1:gFx+x8UowdsKA9AchylcLynDq+nNFfI8FkUZdN/jGCU=
 github.com/rs/xhandler v0.0.0-20160618193221-ed27b6fd6521/go.mod h1:RvLn4FgxWubrpZHtQLnOf6EwhN2hEMusxZOhcW9H3UQ=
 github.com/russross/blackfriday v1.5.2/go.mod h1:JO/DiYxRf+HjHt06OyowR9PTA263kcR/rfWxYHBV53g=
diff --git a/mapper/transaction.go b/mapper/transaction.go
index 0594233b..79eba2e8 100644
--- a/mapper/transaction.go
+++ b/mapper/transaction.go
@@ -1,9 +1,9 @@
 package mapper
 
 import (
+	"fmt"
 	"log"
 	"math/big"
-	"reflect"
 	"strings"
 
 	ethtypes "github.com/ava-labs/coreth/core/types"
@@ -77,25 +77,21 @@ func Transaction(
 	}, nil
 }
 
-func CrossChainTransactions(
+func crossChainTransaction(
+	rawIdx int,
 	avaxAssetID string,
-	block *ethtypes.Block,
-) ([]*types.Transaction, error) {
-	transactions := []*types.Transaction{}
-
-	extra := block.ExtData()
-	if len(extra) == 0 {
-		return transactions, nil
+	tx *evm.Tx,
+) ([]*types.Operation, error) {
+	var (
+		ops = []*types.Operation{}
+		idx = int64(rawIdx)
+	)
+
+	// Prepare transaction for ID calcuation
+	if err := tx.Sign(codecManager, nil); err != nil {
+		return nil, err
 	}
 
-	tx := &evm.Tx{}
-	if _, err := codecManager.Unmarshal(extra, tx); err != nil {
-		return transactions, err
-	}
-
-	var idx int64
-	ops := []*types.Operation{}
-
 	switch t := tx.UnsignedAtomicTx.(type) {
 	case *evm.UnsignedImportTx:
 		// Create de-duplicated list of input
@@ -130,6 +126,7 @@ func CrossChainTransactions(
 					Currency: AvaxCurrency,
 				},
 				Metadata: map[string]interface{}{
+					"tx":            t.ID().String(),
 					"tx_ids":        txIDs,
 					"blockchain_id": t.BlockchainID.String(),
 					"network_id":    t.NetworkID,
@@ -161,6 +158,7 @@ func CrossChainTransactions(
 					Currency: AvaxCurrency,
 				},
 				Metadata: map[string]interface{}{
+					"tx":                t.ID().String(),
 					"blockchain_id":     t.BlockchainID.String(),
 					"network_id":        t.NetworkID,
 					"destination_chain": t.DestinationChain.String(),
@@ -172,9 +170,53 @@ func CrossChainTransactions(
 			idx++
 		}
 	default:
-		panic("Unsupported transaction:" + reflect.TypeOf(t).String())
+		return nil, fmt.Errorf("Unsupported transaction: %T", t)
+	}
+	return ops, nil
+}
+
+func CrossChainTransactions(
+	avaxAssetID string,
+	block *ethtypes.Block,
+	ap5Activation uint64,
+) ([]*types.Transaction, error) {
+	transactions := []*types.Transaction{}
+
+	extra := block.ExtData()
+	if len(extra) == 0 {
+		return transactions, nil
+	}
+
+	// Initialize Atomic Transactions
+	var atomicTxs []*evm.Tx
+	if block.Time() < ap5Activation {
+		// Prior to Apricot Phase 5, there was only one atomic transaction per
+		// block.
+		tx := new(evm.Tx)
+		if _, err := codecManager.Unmarshal(extra, tx); err != nil {
+			return nil, err
+		}
+		atomicTxs = []*evm.Tx{tx}
+	} else {
+		if _, err := codecManager.Unmarshal(extra, &atomicTxs); err != nil {
+			return nil, fmt.Errorf("failed to unmarshal atomic tx (AP5) due to %w", err)
+		}
+	}
+
+	ops := []*types.Operation{}
+	for _, tx := range atomicTxs {
+		txOps, err := crossChainTransaction(len(ops), avaxAssetID, tx)
+		if err != nil {
+			return nil, err
+		}
+		ops = append(ops, txOps...)
 	}
 
+	// TODO: migrate to using atomic transaction ID instead of marking as a block
+	// transaction
+	//
+	// NOTE: We need to be very careful about this because it will require
+	// integrators to re-index the chain to get the new result.
 	transactions = append(transactions, &types.Transaction{
 		TransactionIdentifier: &types.TransactionIdentifier{
 			Hash: block.Hash().String(),
diff --git a/mapper/types.go b/mapper/types.go
index ae62fa7f..98859068 100644
--- a/mapper/types.go
+++ b/mapper/types.go
@@ -1,6 +1,8 @@
 package mapper
 
 import (
+	"github.com/ava-labs/coreth/params"
+
 	"github.com/coinbase/rosetta-sdk-go/types"
 )
 
@@ -28,6 +30,9 @@ const (
 )
 
 var (
+	MainnetAP5Activation = params.AvalancheMainnetChainConfig.ApricotPhase5BlockTimestamp
+	FujiAP5Activation    = params.AvalancheFujiChainConfig.ApricotPhase5BlockTimestamp
+
 	StageBootstrap = &types.SyncStatus{
 		Synced: types.Bool(false),
 		Stage:  types.String("BOOTSTRAP"),
diff --git a/service/config.go b/service/config.go
index 6e685b9b..95362cab 100644
--- a/service/config.go
+++ b/service/config.go
@@ -14,6 +14,9 @@ type Config struct {
 	NetworkID        *types.NetworkIdentifier
 	GenesisBlockHash string
 	AvaxAssetID      string
+
+	// Upgrade Times
+	AP5Activation uint64
 }
 
 const (
diff --git a/service/rosetta.go b/service/rosetta.go
index c898c9af..4c23af8b 100644
--- a/service/rosetta.go
+++ b/service/rosetta.go
@@ -1,7 +1,7 @@
 package service
 
 const (
-	NodeVersion       = "1.6.5"
-	MiddlewareVersion = "0.0.19"
+	NodeVersion       = "1.7.0"
+	MiddlewareVersion = "0.0.20"
 	BlockchainName    = "Avalanche"
 )
diff --git a/service/service_block.go b/service/service_block.go
index 39e8fe6c..3fe3bd14 100644
--- a/service/service_block.go
+++ b/service/service_block.go
@@ -200,7 +200,7 @@ func (s *BlockService) parseCrossChainTransactions(
 ) ([]*types.Transaction, *types.Error) {
 	result := []*types.Transaction{}
 
-	crossTxs, err := mapper.CrossChainTransactions(s.config.AvaxAssetID, block)
+	crossTxs, err := mapper.CrossChainTransactions(s.config.AvaxAssetID, block, s.config.AP5Activation)
 	if err != nil {
 		return nil, wrapError(errInternalError, err)
 	}