While it may have seemed like Helen was on some sort of vacation, she was not, she was doing her job watching the rear of the group, and with the retreat, the 'rear' of the group became the most important part to defend as her Kylie skimmed along the ground, and she brought her aether projectors to bare. "Taisa! Get down and stay down, I'm going to light them up... furthermore; if we all end up as zombies, before then, I want you to know I told you so." She spoke to the group as a whole, before she went about unleashing a pair of steady beams of aether into the following horde, followed by a pair of shots from her shoulder-cannon, aimed to the back of the group to disrupt their advance.
As Helen skimmed along the ground, Helen came to the firm conclusion that carrying on as they were was not going to end up well for them, then she glanced back to see Sune handing the launcher to Hanako. "Bringing the cave down won't do much good, they'll just mow right through the rock and ice unless we bring the whole thing down." Helen spoke her doubts, before she decided to make the situation come to a sharp conclusion. She unleashed a few more rounds from her shoulder cannon... oddly, aiming past the horde, and for beyond the door behind them all. After the confined aetheric explosions, she carefully targeted the last round in the magazine.
"Sune, Takeyu, move into line-of-sight between the Taisa and the location that my rail gun has targeted! Fire in the hole!" Helen instructed sharply, before she unleashed the last round in her magazine, a special-occasion round of sorts, a single antimatter round which she made sure to target beyond the door, and inside of the facility. Clearing the shot's path with an extended blast from her forearm projectors, she unleashed the round to follow the same trajectory as the aether which lead the way prior to the shot.
With the round in-air, Helen focused the CFS of her Kylie to greater improve protection to the forward section, weakening the cohesion of the universal distortion in the rear of the field, to better favor defending the group from the inevitable surge of heat from the blast that was to come, as well as keeping the oncoming horde from advancing as she skimmed the ground to continue the retreat.