Yes, that is expected. The "Elast" has very high defence - as stated when you entered the dungeon for the first time (and they have the lowest attack). Only way to kill it (in early game) is through giving it a candy. I designed it to be like this - other wise people just go killing all enemies without using the function "feeding candies". It is also a practice for the players - fighting without using candies WILL NOT WORK here.
Another reason for this is to make them an obstacle when you want to escape from the ruins: they will not do any damage to you, but they are here to stop you.
Thanks again for playing!