Learn Turkish: Sözde şövalye kılıcıyla ejderhaya saldırmışmış. - The so-called knight supposedly attacked the dragon with his sword.

This double -mış is the compound inferential of disbelief or sarcasm, which is the focus of this lesson. The first -mış is the standard evidential past tense (meaning you heard about the attack). The second -mış adds heavy skepticism, irony, or sarcasm. It shows that the speaker is reporting the claim but thinks it is completely ridiculous or untrue.

Since -mışmış already shows disbelief, why is the word sözde in the sentence?

Sözde reinforces the sarcasm, but it specifically targets the noun next to it. It translates to "so-called" or "supposedly." So sözde şövalye means "the so-called knight." While -mışmış expresses disbelief about the action (the attacking), sözde expresses disbelief about the person's status as a real knight.

Why is the dragon in the dative case (ejderhaya) instead of the accusative case (ejderhayı)?

In English, you attack a direct object, but the Turkish verb saldırmak (to attack) always takes the dative case (-e or -a). You can think of it as directing your aggression towards a target. Since ejderha ends in a vowel, it needs the buffer consonant -y- before the dative suffix -a.

Can you break down the suffixes on kılıcıyla?