diff --git a/pkg/cascadekit/verify.go b/pkg/cascadekit/verify.go
index 74331dde..8fd90beb 100644
--- a/pkg/cascadekit/verify.go
+++ b/pkg/cascadekit/verify.go
@@ -1,27 +1,57 @@
 package cascadekit
 
 import (
+	"encoding/base64"
+	"fmt"
+
+	actionkeeper "github.com/LumeraProtocol/lumera/x/action/v1/keeper"
 	"github.com/LumeraProtocol/supernode/v2/pkg/codec"
 	"github.com/LumeraProtocol/supernode/v2/pkg/errors"
-	"github.com/LumeraProtocol/supernode/v2/pkg/utils"
 )
 
-// VerifySingleBlockIDs enforces single-block layouts and verifies that the
-// symbols and block hash of ticket and local layouts match for block 0.
-func VerifySingleBlockIDs(ticket, local codec.Layout) error {
-	if len(ticket.Blocks) != 1 || len(local.Blocks) != 1 {
-		return errors.New("layout must contain exactly one block")
+// Verifier is a function that verifies the signature over data using the signer's on-chain pubkey.
+// It should return nil if signature is valid; otherwise an error.
+type Verifier func(data []byte, signature []byte) error
+
+// VerifyStringRawOrADR36 verifies a signature over a message string in two passes:
+//  1. raw:   verify([]byte(message), sigRS)
+//  2. ADR-36: build amino-JSON sign bytes with data = base64(message) and verify
+//
+// The signature is provided as base64 (DER or 64-byte r||s), and coerced to 64-byte r||s.
+func VerifyStringRawOrADR36(message string, sigB64 string, signer string, verify Verifier) error {
+	sigRaw, err := base64.StdEncoding.DecodeString(sigB64)
+	if err != nil {
+		return fmt.Errorf("invalid base64 signature: %w", err)
 	}
-	if err := utils.EqualStrList(ticket.Blocks[0].Symbols, local.Blocks[0].Symbols); err != nil {
-		return errors.Errorf("symbol identifiers don't match: %w", err)
+	sigRS, err := actionkeeper.CoerceToRS64(sigRaw)
+	if err != nil {
+		return fmt.Errorf("coerce signature: %w", err)
 	}
-	if ticket.Blocks[0].Hash != local.Blocks[0].Hash {
-		return errors.New("block hashes don't match")
+	if err := verify([]byte(message), sigRS); err == nil {
+		return nil
 	}
-	return nil
+	dataB64 := base64.StdEncoding.EncodeToString([]byte(message))
+	doc, err := actionkeeper.MakeADR36AminoSignBytes(signer, dataB64)
+	if err != nil {
+		return fmt.Errorf("build adr36 doc: %w", err)
+	}
+	if err := verify(doc, sigRS); err == nil {
+		return nil
+	}
+	return fmt.Errorf("signature verification failed")
+}
+
+// VerifyIndex verifies the creator's signature over indexB64 (string), using the given verifier.
+func VerifyIndex(indexB64 string, sigB64 string, signer string, verify Verifier) error {
+	return VerifyStringRawOrADR36(indexB64, sigB64, signer, verify)
+}
+
+// VerifyLayout verifies the layout signature over base64(JSON(layout)) bytes.
+func VerifyLayout(layoutB64 []byte, sigB64 string, signer string, verify Verifier) error {
+	return VerifyStringRawOrADR36(string(layoutB64), sigB64, signer, verify)
 }
 
-// VerifySingleBlock checks that a layout contains exactly one block.
+// VerifySingleBlock ensures the RaptorQ layout contains exactly one block.
 func VerifySingleBlock(layout codec.Layout) error {
 	if len(layout.Blocks) != 1 {
 		return errors.New("layout must contain exactly one block")
diff --git a/sdk/action/client.go b/sdk/action/client.go
index d5fdf410..81aa806b 100644
--- a/sdk/action/client.go
+++ b/sdk/action/client.go
@@ -318,13 +318,15 @@ func (c *ClientImpl) BuildCascadeMetadataFromFile(ctx context.Context, filePath
 // GenerateStartCascadeSignatureFromFile computes blake3(file) and signs it with the configured key.
 // Returns base64-encoded signature suitable for StartCascade.
 func (c *ClientImpl) GenerateStartCascadeSignatureFromFile(ctx context.Context, filePath string) (string, error) {
+	// Compute blake3(file), encode as base64 string, and sign the string bytes
 	h, err := utils.Blake3HashFile(filePath)
 	if err != nil {
 		return "", fmt.Errorf("blake3: %w", err)
 	}
-	sig, err := keyringpkg.SignBytes(c.keyring, c.config.Account.KeyName, h)
+	dataHashB64 := base64.StdEncoding.EncodeToString(h)
+	sig, err := keyringpkg.SignBytes(c.keyring, c.config.Account.KeyName, []byte(dataHashB64))
 	if err != nil {
-		return "", fmt.Errorf("sign hash: %w", err)
+		return "", fmt.Errorf("sign hash string: %w", err)
 	}
 	return base64.StdEncoding.EncodeToString(sig), nil
 }
diff --git a/sdk/task/helpers.go b/sdk/task/helpers.go
index 2e9ee4c3..aac0fed1 100644
--- a/sdk/task/helpers.go
+++ b/sdk/task/helpers.go
@@ -2,12 +2,12 @@ package task
 
 import (
 	"context"
-	"encoding/base64"
 	"fmt"
 	"math/big"
 	"os"
 	"sort"
 
+	"github.com/LumeraProtocol/supernode/v2/pkg/cascadekit"
 	"github.com/LumeraProtocol/supernode/v2/pkg/utils"
 	"github.com/LumeraProtocol/supernode/v2/sdk/adapters/lumera"
 )
@@ -74,26 +74,13 @@ func (m *ManagerImpl) validateSignature(ctx context.Context, action lumera.Actio
 		return fmt.Errorf("failed to decode cascade metadata: %w", err)
 	}
 
-	// Extract the base64-encoded data hash from the metadata
-	base64EnTcketDataHash := cascadeMetaData.DataHash
+	// Extract the base64-encoded data hash string from the metadata
+	dataHashB64 := cascadeMetaData.DataHash
 
-	// Decode the data hash from base64 to raw bytes
-	dataHashBytes, err := base64.StdEncoding.DecodeString(base64EnTcketDataHash)
-	if err != nil {
-		return fmt.Errorf("failed to decode data hash: %w", err)
-	}
-
-	// Decode the provided signature from base64 to raw bytes
-	signatureBytes, err := base64.StdEncoding.DecodeString(signature)
-	if err != nil {
-		return fmt.Errorf("failed to decode signature: %w", err)
-	}
-
-	// Verify the signature using the Lumera client
-	// This checks if the signature was produced by the action creator
-	// for the given data hash
-	err = m.lumeraClient.VerifySignature(ctx, action.Creator, dataHashBytes, signatureBytes)
-	if err != nil {
+	// Verify using cascadekit helper (raw -> ADR-36)
+	if err := cascadekit.VerifyStringRawOrADR36(dataHashB64, signature, action.Creator, func(data, sig []byte) error {
+		return m.lumeraClient.VerifySignature(ctx, action.Creator, data, sig)
+	}); err != nil {
 		m.logger.Error(ctx, "Signature validation failed", "actionID", action.ID, "error", err)
 		return fmt.Errorf("signature validation failed: %w", err)
 	}
diff --git a/supernode/cascade/download.go b/supernode/cascade/download.go
index 944e7d84..7378f920 100644
--- a/supernode/cascade/download.go
+++ b/supernode/cascade/download.go
@@ -2,7 +2,6 @@ package cascade
 
 import (
 	"context"
-	"encoding/base64"
 	"encoding/json"
 	"fmt"
 	"os"
@@ -117,11 +116,9 @@ func (task *CascadeRegistrationTask) VerifyDownloadSignature(ctx context.Context
 		return fmt.Errorf("get action for signature verification: %w", err)
 	}
 	creator := act.GetAction().Creator
-	sigBytes, err := base64.StdEncoding.DecodeString(signature)
-	if err != nil {
-		return fmt.Errorf("invalid base64 signature: %w", err)
-	}
-	if err := task.LumeraClient.Verify(ctx, creator, []byte(actionID), sigBytes); err != nil {
+	if err := cascadekit.VerifyStringRawOrADR36(actionID, signature, creator, func(data, sig []byte) error {
+		return task.LumeraClient.Verify(ctx, creator, data, sig)
+	}); err != nil {
 		return err
 	}
 	return nil
diff --git a/supernode/cascade/helper.go b/supernode/cascade/helper.go
index 2d204c52..cbc5699b 100644
--- a/supernode/cascade/helper.go
+++ b/supernode/cascade/helper.go
@@ -2,7 +2,6 @@ package cascade
 
 import (
 	"context"
-	"encoding/base64"
 	"strconv"
 
 	"cosmossdk.io/math"
@@ -87,11 +86,9 @@ func (task *CascadeRegistrationTask) validateIndexAndLayout(ctx context.Context,
 	if err != nil {
 		return cascadekit.IndexFile{}, nil, err
 	}
-	creatorSig, err := base64.StdEncoding.DecodeString(creatorSigB64)
-	if err != nil {
-		return cascadekit.IndexFile{}, nil, err
-	}
-	if err := task.LumeraClient.Verify(ctx, creator, []byte(indexB64), creatorSig); err != nil {
+	if err := cascadekit.VerifyIndex(indexB64, creatorSigB64, creator, func(data, sig []byte) error {
+		return task.LumeraClient.Verify(ctx, creator, data, sig)
+	}); err != nil {
 		return cascadekit.IndexFile{}, nil, err
 	}
 	// Decode index
@@ -104,14 +101,13 @@ func (task *CascadeRegistrationTask) validateIndexAndLayout(ctx context.Context,
 	if err != nil {
 		return cascadekit.IndexFile{}, nil, err
 	}
-	if err := cascadekit.VerifySingleBlock(layout); err != nil {
-		return cascadekit.IndexFile{}, nil, err
-	}
-	layoutSig, err := base64.StdEncoding.DecodeString(indexFile.LayoutSignature)
-	if err != nil {
-		return cascadekit.IndexFile{}, nil, err
+	// Enforce single-block layout for Cascade
+	if len(layout.Blocks) != 1 {
+		return cascadekit.IndexFile{}, nil, errors.New("layout must contain exactly one block")
 	}
-	if err := task.LumeraClient.Verify(ctx, creator, layoutB64, layoutSig); err != nil {
+	if err := cascadekit.VerifyLayout(layoutB64, indexFile.LayoutSignature, creator, func(data, sig []byte) error {
+		return task.LumeraClient.Verify(ctx, creator, data, sig)
+	}); err != nil {
 		return cascadekit.IndexFile{}, nil, err
 	}
 	return indexFile, layoutB64, nil