Stage 30 Cleared!!

The Officer Academy is locked, and growth is glacial for free-to-play players. It's quite tough unless you get the unique skills for Shotgunners and Machine Gunners with Legend Gems and Epic Gems through the Baptism. Also, if you don't carry over 5 Shields or 5 First Aid Kits from Stage 29, your healing won't keep up. I also unlocked the Operation Lab and leveled up the Armory to Level 30 or higher with Epic or better rarity. For myself, I've strictly selected only Attack and Damage stats. With this setup, I barely managed to clear it using continues. Ultimately, I had 2 First Aid Kits (5 uses) and 1 Shield (5 uses), and healing was still just barely enough.