|Yu-Gi-Oh! Card Singles - Tip Card |
The effect of "Thunder Dragon" allows you to discard it from your hand to add two other copies of "Thunder Dragon" from your Deck into you hand. This effect may not seem very good on its own, but it can be a part of many combos.
For example, if you had "Muka Muka" on the field, "Thunder Dragon" just helped it become 300 ATK points stronger. If you have "Skull Lair" on the field, now you have 1 more Monster Card in the Graveyard to use for its effect, without decreasing the amount of cards in your hand (if you can add 2 "Thunder Dragon"'s, in fact you increased it)!