"Mage Power" is good with this card because you will be relying on defensive Spells and Traps such as "Book of Moon" and "Waboku" to protect "Rapid Warrior".
Equip this card with "Armor Breaker" to allow you to gain card advantage by destroying an opponent's card each time this card inflicts battle damage.
When this monster is being attacked by your opponent's monster with a very high ATK, use "Power Frame" to negate the attack and gain the difference in ATK. Then, you can attack directly using your opponent's own strength against them.
Equip an opponent's monster with "Darkworld Shackles" and activate "Kaiser Colosseum". Your opponent won't be able to attack nor Summon other monsters and receive damage, then keep attacking with "Rapid Warrior".