(The Founder knocks out O'Brien as the blast doors come down. Odo grabs him.)
COMPUTER: Engine room sealed. (The founder morphs his arm into Odo's abdomen, and Odo starts to ripple.)
FOUNDER: Why are you protecting these solids? You don't belong with them. You belong with us.
COMPUTER: Auto-destruct in three minutes.
FOUNDER: Let go. Don't you see? You've lost. It's too late for you to help them but it's not too late to help yourself. Link with me, Odo. We can escape together.
ODO: I don't think so. (Odo morphs his hands into the founder as his body becomes solid again. The founder goes gooey and Odo picks him up and pushes him against the warp core. The energy discharge throws Odo off as the founder fries.)
COMPUTER: Auto-destruct in two minutes.
ODO: (to dazed O'Brien) You have to regain control of the ship. (The founder part reforms, looking very desiccated.)
ODO: I never wanted to harm you.
Just before this the other changeling is hurting odo or at least appears to be. Is odo the first to harm or kill another changeling?
Now that I think of it, since this changeling attacked odo before odo attacked him back, wouldn't this be the first example of one changeling harming another?
Why isn't it possible that a changeling harmed another before this episode, regardless of what the female founder (whose morals are questionable at best) states many times?
If there are any writers notes, or EU info available that would be more then welcomed.