Use this card to revive "Wind-Up Warrior", then use its effect to pump "Rat" to Level 4, and Xyz Summon.
Use this card to revive "Wind-Up Hunter", then you can use this card for Tribute to active its effect.
You can produce an OTK by using this card, at least one other copy of this card in your graveyard, "Final Attack Orders" and "Cannon Soldier". Just have "Cannon Soldier" and "Final Attack Orders" face up on the field and use the effect of "Wind-Up Rat" to bring back another "Wind-Up Rat". The revived one will be switched to attack position, so you can use its effect immediately. Use the effect of "Cannon Soldier" to tribute the used Rat for damage, then bring it back with the other "Rat". Continue to follow this loop until your opponent has no more life points.