Boss Moves: Sucker Punch + Focus Blast
Weather: Rain
Time taken: ~165 seconds
Attempts: 2 (on my first, timed out despite my Dragonite apparently dealing the killer OR with 5 seconds left).
Team:
1. L30 Tyranitar, Bite/Crunch, 13A/15D/13S
2. L30 Gengar, Hex/SBall, 14A/14D/10S
3. L30 Espeon, Conf/FS, 12A/15D/14S
4. L30 Alakazam, PC/FS, 13A/15D/15S
5. L30 Exeggutor, Conf/Psyc, 13A/14D/14S
6. L30 Dragonite, DT/OR, 14A/11D/15S
Dodging: Only for Focus Blast despite Sucker Punch being super-effective against Psychic-types. Missed several dodges on my first attempt due to reacting too early. Dodging on my second attempt was easy as I had gotten used to the timing.
Caught IVs: 10A/13D/10S or 11A/13D/9S
Caught moves: Sucker Punch + Focus Blast (ROFL)
Of course, not spending any dust or TMs on this Gengar. A Charged TM was among my rewards; hooray!
For my next Gengar solo, should I stick with this team or switch the Alakazam with my other one (L30, 15A/15D/14S, with Conf/FS)?
Swap out the Exeggutor for the other Alakazam.
Also, your Gengar has to be 10/13/10, because it is a raid catch.
I almost failed a Hex/FB cloudy Gengar solo 2 days ago, due to "twisted reality" glitches. By the time I finished the final attempt (which thankfully was successful), the raid timer was already over.
Next time, try to do FB Gengar in cloudy weather, for the weather boost!
It's counterintuitive, but sometimes glass cannons actually help survivability, because the high DPS allows you to knock out the boss sooner. I observed this the first time I soloed Omastar, when on the first two attempts, I had tankier but lower DPS mons in the last two spots (first Machamp and Poliwrath, then Raikou and Zapdos), and both times, my last mon was knocked out with a few seconds left in the battle.
Then, I put glassy but high-DPS Victreebels (double super effective) in the last two slots, and won with 20 seconds remaining, and the last Victreebel still having half its health. Survivability means surviving longer than the boss, not necessarily surviving for 180 seconds.
Congrats! Gengar is in my opinion a really fun boss to solo. For your next one, I'd replace the Exeggutor with the other Alakazam as someone already said. Exeggutor doesn't have much higher survivability due to typing and Alakazam deals better damage.
Good luck on your further attempts! Shadow Ball has a similar ridiculously late dodge window as Focus Blast, while Sludge Bomb is a lot faster.
You can do Shadow Ball but you will need to hit those dodges. The psychic glass cannons can survive two dodged ShB, Gengar might only be able to dodge one. If your Houndooms are near level 30 with double dark moveset they are worth using against ShB regardless of IV. EQ Groudon is actually overall even better than TTar so definitely use that if you have it powered.
With problems in survivability, Dragonite, Lugia, Moltres and Rhydon can be helpful.
