>>27138557You're gonna have to mix it up depending on what character you are fighting, but one thing stays constant. Get synergy. Gengar relies on synergy more than pretty much every other character, it seems. Gengar's grab does shit damage, but heals and builds synergy, so get those grab reads. Also, in dual phase, occassionally throw out curse if you read them going for a ground based attack. Don't overuse it since it costs HP, but it does shitloads if it hits and it builds synergy even on whiff.
In field, use all your projectiles and be a huge cunt. If they try to approach you, you can attempt to "counter" them with back X (strong attack). The move is slow as shit, but it nullifies some projectiles and has a big ass hitbox around Gengar. Good to use against people on wakeup since they won't be able to punish it.
In dual phase, if you manage to put someone into a hard knock down, charge up a shadow ball over them. Unless they have a move with invincible start up like Lucario or Pikachu, they are limited to 3 options: Block, Counter Attack, and getting hit. If they block, you can do anything you want since you have frame advantage. If they counter attack the shadow ball, you get a free critical grab/hypnosis. If they get hit, you can confirm off it for a combo.
If you put them into soft knock down, try going for charged X (strong attack). It'll break through counter attacks on wake up (barring one frame ones like Lucario/Pikachu's "shoryukens") and if you time it right, will beat out regular attacks. Speaking of, on wake up you can use high stance Y (weak attack) as a bootleg Shoryuken. It's not safe, but it has a SHITLOAD of invul.
If the opponent tries to zone you in duel, you gotta pressure them hard with shadow punch and shadow ball. You can combo from midscreen if you hit them with a fully charged shadow punch.
Also, learn how to Astonish Loop, especially off Y (weak attack).
https://www.youtube.com/watch?v=nrPgm0I1GkY 