In the new tutorial, I met a bug where I have to use my 3 swords to kill 2 speartons instead of just one. As a result, I couldn't finish the tutorial and had to restart it.

Same, I got that too.

In SE or campaign? In SE I didn't face this.

SE. Did you try the tutorial after the new update?

Yes. It was perfectly normal. I tried it JUST AFTER the new update.

Lol then just wait for the castle archer to finish them off before attacking those speartons

Huh? What do you mean.

lol I pwned those speartons, just retreat and let your castle archer shoot at him first, then go back

Oh. Well I still don't understand? so you let the castle kill him, but that still doesn't fix the bug.