Originally Posted by Dorei0sama

Because there are 2 nodes in short distance to go to mini boss, so you need to have a high speed team to pass those 2 (speedy team tends to go farer than normal team). I did one auto run after this, and my 700 speed unit accidentally land on the mini boss (on the same pattern) but chance is slimmer on 700 speed. I think the higher speed the higher chance to land on it. There are many nods so it's easier to manage with two team (one should have high speed other on should not be stronger than the boss in case it pass the upper nod). Fortunately, i have 2 allies with speedy helper team.

Those spinning arrow nodes are purely random (known here as RNG nodes) in which direction they send your unit. Speed is irrelevant for those. Where Speed DOES matter is path length (think it's 10-3 where this is a HUGE issue) and sometimes triggering the fixed arrow nodes (where they switch directions every time you run over them, manipulating speeds so a specific squad goes down a certain path sometimes helps). The Halloween event favored ALL 5 squads having low speeds to maximize time spent on the map for event item farming, but that's a rare case.