Well, I beat it! The final battle took me about 15 minutes, definitely the longest one yet... and that is the best ending. A perfect blend of serious and fun. For the 10th wave of Himawari ward, it's a good idea to play earlier areas and farm metachips, then pour them into generator and armour upgrades for all your sentinels you plan to bring with you. Pick teams that have a good balance, but are god at providing support units. For myself, I brought:
1st gen: Ogata and Hijiyama. Make sure their Demolisher blades are maxed out and they can have enough EP to use them repeatedly.
2nd Gen: I brought Kurabe, but you can bring any of them as long as they have centry guns and a good set of medium range weapons.
3rd Gen. Minami and Miura, but this again depends on which sentinels are better equipped.
4th Gen: Takamiya and Gouto, both with interceptors and multilock missiles
Deploy as many autonomous units so they can deal with nearby targets, which makes your job easier. Hunt around with your 1st gen sentinels if they have good enough armour and duability, and se demolisher blades on everything as much as you can, rush attack when you can't. If you use two demolisher blades on the same unit and it doesn't go down, chances are it's the hiquad DX, which also has an attack of its own that can deal serious damage, so be careful. Other than that, make sure the map is blanketted with centry guns and interceptors. And make it a point to use 3rd gen sentinels at their best range and with their AOE attacks. Hope this helps somebody.
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