Many of the cards that are circulating in duel masters have this little text that says "While you have at least 1 Human/Armorloid/Cyber Lord etc. in the battle zonee, this creature....etc" Follow by some effect that is mediocre to really good. Now it might seem like an easy thing to pull off, but dont be decieved. Rarely will you have the right two cards in your hand or let alone the battle zone to pull of their effects. Chances are that one of the components that you need will be destroyed or not in the right place at the right time. Some of these cards are the fire cards Armored Walker Urberion and the Fatal Attacker Horvath and the water card Illusionary Merfolk. To pull of some of these abillites, you would have to fill your deck with creatures of the right 'type" which could be cards that are crappier than cards you could have put in. On the flip side if you happen to come across these cards together the effects can be wonderful. So i would recommend maybe playing one of each need component only if both components are actually worth playing. Thats my 2 cents.