diff --git a/game.go b/game.go
index 777b39e..7fa5ec9 100644
--- a/game.go
+++ b/game.go
@@ -252,12 +252,11 @@ func (g *Game) combat(atk, def *Piece) (int, error) {
 	if atk == nil || def == nil {
 		return 0, errors.New("invalid attacker or defender")
 	}
-	if atk.Hidden {
-		return 0, errors.New("trying to attack with a piece we know nothing about?")
-	}
-	if def.Hidden {
+	if def.Hidden && def.Rank == Unknown {
 		return 0, errors.New("defender has not been revealed to us")
 	}
+	//reveal attacker
+	atk.Hidden = false
 	//handle special cases first
 	//miner hitting bomb
 	if atk.Rank == Miner && def.Rank == Bomb {
diff --git a/piece.go b/piece.go
index 80f8a65..e571f26 100644
--- a/piece.go
+++ b/piece.go
@@ -14,6 +14,7 @@ const (
 	General
 	Marshal
 	Bomb
+	Unknown
 )
 
 //Piece :game piece
@@ -36,15 +37,16 @@ func NewPieceFromInt(r int, o Colour) *Piece {
 func NewPiece(r Rank, o Colour) *Piece {
 	return &Piece{
 		Rank:   r,
-		Owner:  o,
-		Hidden: false,
-	}
-}
-
-//NewHiddenPiece creates a new hidden piece
-func NewHiddenPiece(o Colour) *Piece {
-	return &Piece{
 		Owner:  o,
 		Hidden: true,
 	}
 }
+
+//NewUnknownPiece creates a new hidden piece
+func NewUnknownPiece(o Colour) *Piece {
+	return &Piece{
+		Owner:  o,
+		Rank:   Unknown,
+		Hidden: true,
+	}
+}
diff --git a/rank_enumer.go b/rank_enumer.go
index da53b83..6acd9b9 100644
--- a/rank_enumer.go
+++ b/rank_enumer.go
@@ -7,9 +7,9 @@ import (
 	"fmt"
 )
 
-const _RankName = "FlagSpyScoutMinerCaptainGeneralMarshalBomb"
+const _RankName = "FlagSpyScoutMinerCaptainGeneralMarshalBombUnknown"
 
-var _RankIndex = [...]uint8{0, 4, 7, 12, 17, 24, 31, 38, 42}
+var _RankIndex = [...]uint8{0, 4, 7, 12, 17, 24, 31, 38, 42, 49}
 
 func (i Rank) String() string {
 	if i < 0 || i >= Rank(len(_RankIndex)-1) {
@@ -18,7 +18,7 @@ func (i Rank) String() string {
 	return _RankName[_RankIndex[i]:_RankIndex[i+1]]
 }
 
-var _RankValues = []Rank{0, 1, 2, 3, 4, 5, 6, 7}
+var _RankValues = []Rank{0, 1, 2, 3, 4, 5, 6, 7, 8}
 
 var _RankNameToValueMap = map[string]Rank{
 	_RankName[0:4]:   0,
@@ -29,6 +29,7 @@ var _RankNameToValueMap = map[string]Rank{
 	_RankName[24:31]: 5,
 	_RankName[31:38]: 6,
 	_RankName[38:42]: 7,
+	_RankName[42:49]: 8,
 }
 
 // RankString retrieves an enum value from the enum constants string name.