Pleakley managing to capture 613 and saving him from being crushed by falling rocks and stalactites in the lava tube.
Splodyhead and Stitch vs. Slushy, an epic five minute battle that has everything from More Dakka fireballs and icicles, frozen tornados and giant monsters made of fire and ice.
Jumba: "Elemental evil genius experiments about to join in epic battle, and I forgot camera."note Funny thing about that comment, he managed to show a recording of that battle to the head of the Evil Genius Organization in "Ace".
Hämsterviel taking out Stitch with a plasma cannon. Double awesome as he had made the plasma cannon out of the playthings in his gerbil cage.
Stitch and 625's fight on top of Gantu's ship. Bonus points for 625 getting the upper-hand with some quick thinking.
More bonus points if you consider that his sudden competence is not even anAss Pull: 625 has the same skills and powers Stitch has. That wasn't just "quick", it was "faster-than-a-supercomputer" thinking.