Quick an easy help with custom cards.

[Naoto10281]

Working on some cards and I'm very new at this but I was wondering if it's possible to make an additional cost of a creature be that you have to have a creature of the same type on the field already.

Example -
Cost 2BB
To play CARDNAME you must control a Dragon.

I'm trying to get it so you can play a card with morph OR if you have a dragon on the field you can play it normally and gain a few effects from it.

Please and thank you in advance.