Yu-Gi-Oh!, Season 3: Enter the Shadow Realm

Yami-Yugi:
Marik's fusion monster is regenerating itself!

Yami-Marik:
Precisely! That's because my monster has the combined power of Egyptian God Slime and Revival Jam! My plan's complete. Thanks to my invincible defense monster, my Life Points can no longer be damaged. Therefore, defeating me is impossible, Pharaoh! Don't you see? This was my plan from the start, and you fell for it! How naive of you!

Tristan:
That's insane!

Joey:
I'm not worried about a thing, Tristan. Yugi will figure out how to take that big slime ball down!

Duke:
Well, it doesn't look too promising from where I'm standing!

Tea:
Come on.

Mokuba:
Now what?

Kaiba:
(thinking) I knew this was all part of Marik's strategy all along! He let Yugi's Obelisk the Tormentor attack him on purpose! That allowed Marik to create an unstoppable Obelisk clone! Now whenever Yugi attacks it, Marik's Egyptian God Slime will absorb the blow and then regenerate itself!