Question about Elphael Brace of the Haligtree

[Clockwork]

So, I just reached Miquella's Haligtree and am proceeding forward.

The place looks nice, and some enemies are easy to kill. Some others are tougher but I supposed that's expected. But what I'm curious about though is the way some of the enemies are spawned together.

There was this area, not far from the beginning of Elphael, where after dodging the ballistae, you have to fight an Erdtree Avatar along with 2 Haligtree Knights, immediately with a grace behind them.

As usual, I take them out one by one to make things easier, although I can't help but wonder: are you supposed to be capable of taking them on all at once?