diff --git a/commands.go b/commands.go
index 7ff7b95..16603a6 100644
--- a/commands.go
+++ b/commands.go
@@ -2,11 +2,9 @@ package main
 
 import (
 	"fmt"
-	"math/rand"
 	"sort"
 	"strconv"
 	"strings"
-	"time"
 )
 
 var commandRegistry map[string]*Command
@@ -176,27 +174,13 @@ var colonizeCommand = &Command{
 	help: "establishes a mining colony on the current system",
 	handler: func(conn *Connection, arg ...string) {
 		system := conn.System()
-		var fn func()
-		fn = func() {
-			reward := int(rand.NormFloat64()*5.0 + 100.0*system.miningRate)
-			if system.colonizedBy != nil {
-				system.colonizedBy.Deposit(reward)
-				fmt.Fprintf(system.colonizedBy, "mining colony on %s pays you %d space duckets. total: %d space duckets.\n", system.name, reward, system.colonizedBy.money)
-			}
-			After(5*time.Second, fn)
-		}
-
-		if system.colonizedBy != nil {
-			system.colonizedBy = conn
-			After(5*time.Second, fn)
-			return
-		}
-
 		if conn.money > 2000 {
 			conn.Withdraw(2000)
+			if system.colonizedBy != nil {
+				fmt.Fprintf(system.colonizedBy, "your colony on %s has been stolen by %s\n", system.Label(), conn.PlayerName())
+			}
 			system.colonizedBy = conn
 			fmt.Fprintf(conn, "set up a mining colony on %s\n", conn.System().name)
-			After(5*time.Second, fn)
 		} else {
 			fmt.Fprintf(conn, "not enough money!  it costs 2000 duckets to start a mining colony\n")
 		}
diff --git a/game.go b/game.go
index a591580..e9a2d88 100644
--- a/game.go
+++ b/game.go
@@ -39,6 +39,9 @@ func NewGame() *Game {
 	if err := game.Create(); err != nil {
 		log_error("unable to create game: %v", err)
 	}
+	for _, system := range index {
+		game.Register(system)
+	}
 	return game
 }
 
diff --git a/system.go b/system.go
index f8fb062..659ec03 100644
--- a/system.go
+++ b/system.go
@@ -24,6 +24,16 @@ type System struct {
 	distances   []Ray
 }
 
+func (s *System) Tick(frame int64) {
+	if s.colonizedBy != nil {
+		s.colonizedBy.Deposit(1)
+	}
+}
+
+func (s *System) Dead() bool {
+	return false
+}
+
 func (s *System) Arrive(conn *Connection) {
 	conn.SetSystem(s)
 	log_info("player %s has arrived at system %s", conn.PlayerName(), s.name)