Running through the middle of this bridge triggers delayed waves of spawns.

about this same last bridge, the long one with the railroad tracks.cast Singularity backwards near the end of the last bridge kill those slowly spawning enemies then run to the bosses, otherwise combat stays 'on' ( see video).use Blink - but save it for key spots, as you only get ~4 casts unfortunately you cannot Blink over the wall like the Warrior Leap.the Smoke Screen spell forces combat to disengage (use at the end, after killing the bosses).the Assault-4 bonus makes BH run even faster while attacking - click to attack a monster as far ahead as you can see - including the other side of the first wall to the left, as pointed out here.they have much faster innate movement speed than mage or warrior.

There's another route that uses the Leap trick - read it here.

Use the Leap trick to go over the first wall to the north (more or less on your left), and again over the next wall to the north (more towards the right this time - try to leap past the last bridge) ( see video).

get a lucky spawn - after you try it a bunch of times you start spawning at other places & eventually you'll spawn a decent ways into the level.

maximize %-movement-speed, not just in Champion Points but also >50% on both Boots & Pants.

don't use minions, they lag behind and attack enemies you'd rather just run past, maintaining combat as 'on'.

reduce enemy level to Normal, level 60 instead of 70.

Eternium champion points