So I know that if Destiny Hero - Diamond Dude hits a normal spell card with its effect only the spell's effect is activated and the cost is vanquished.

My question is, for cards like Rare Value and Crystal Abundance, which parts of the cards are the costs and which parts are the effects?

Rare Value
Normal Spell
Activate only when there are 2 or more "Crystal Beast" cards in your Spell & Trap Card Zone. Your opponent selects 1 "Crystal Beast" card from your Spell & Trap Card Zone and sends it to the Graveyard. Then you draw 2 cards.

Crystal Abundance
Normal Spell
Send 4 "Crystal Beast" cards from your Spell & Trap Card Zone to the Graveyard. Send all cards on the field to the Graveyard. Then, Special Summon as many "Crystal Beast" monsters as possible from your Graveyard, up to the number of your opponent's cards that were sent to the Graveyard by this card's effect.

Rare Value = Effect.

* If "Macro Cosmos" or "Banisher of the Raidance" is on the field, you can still activate "Rare Value", but since the "Crystal Beast" card is not sent to the Graveyard you do NOT draw 2 cards.

If it were a cost, then having either on the field would prevent you from being able to activate it in the first place.



Gem Abundance = cost.

* Sending 4 "Crystal Beast" Monster Cards from your Spell & Trap Card Zone to the Graveyard is a cost to activate this card.

* You cannot activate this card while "Macro Cosmos" is active.




Usually, costs are among the first things said on the card;

"<whatever> to..."

"By <whatever>, you can..."

"You can <effect> by <cost>..."

"<whatever>. <effect>"

...and so on.

If it doesn't appear obvious on the card itself, then one needs to look up the rulings to see if they say it is or not.