My S-rank attempt of Underground Exploration Depth 1, recorded in Update 1.02. I feel like this mission is rather generous when it comes to giving the S-rank, since I took quite a bit of damage.
It seems like you can take a fair bit of damage as long as you descend quickly enough to the bottom. The build I use here was designed for both Attitude Stability and Anti-Energy defense, since I'm bad at avoiding the lasers. The Coral Shield and the Pulse Armor are key for this. Pulse Armor seems to completely deflect the 6-shot burst of the laser, and the Coral Shield really helps reduce damage as you fall, so I wasn't completely fried by the time I hit the bottom.
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