Camillo Gamnitzer, StrateGems 2017
Position: 4Q1b1/1pp2p2/2P2P1n/3N3R/4N1p1/5kPp/p1p4p/r1b2Knr w - - 0 1
 
selfmate in 5

Black: Bg8, b7, c7, f7, Nh6, g4, Kf3, h3, a2, c2, h2, Ra1, Bc1, Ng1, Rh1
White: Qe8, c6, f6, Nd5, Rh5, Ne4, g3, Kf1

1. De5?! thr. shortest (2. Df4+ Lxf4#) L~+! 2. Dxa1...

1. De7! (2. Dxc7! [more threats] Kxe4 3. De5+ Kd3 4. Dc3+ Ke4 5. De3+ Lxe3#; 3. - Kf3? 4. Df4+/De3+ LxD#)
1. - Sf5? 2. Txf5+ Lf4# = also setplay
1. - Tb1 flight-preparing
2. De5! Tb~ → defence-replacement, leaving battery-position instead of battery-fire
3. Sd2+! Lxd2 → without annoying check!
Final: 
4. De2+ Kxg3
5. Dg2+! hxg2#
6. Ke1??

One of CG's favorite themes; quiet destruction of black battery, here once more for an unexpected reason: battery-bishop c1 has to guard e1...   

Some non-thematic attempts:
1. cxb7? (2. Dc6/Da4) Lh7!
1. Dd8?/Dd7?/Dc8?/Db8? (2. Sg5+ Kxg3 3. Dxc7+ Lf4#) Kxe4!