So, just this patch it was established, that the dragon should not have the dragon's tooth effect because...
Well, obviously caster comps wouldn't be able to kill it.
Good riddance! But wait! There's more to be changed.
After the dragon, there's a Rift Herald waiting to be slain and he wears a random complete item.
Correct me if I am wrong, but the item effect applies to the Herald, right?
I ask, because I just ran my entire Gunslinger + frontline team (which proceeded to win1st place ) into a Herald with a Warmog and I was not able to kill the darn thing.
Now Imagine they come with a dragon's tooth and we have the same situation with the dragon all over again.
Long story short: PVE encounters do not need RNG or even variables.