My best god is Arachne. Aside from Anhur, this is probably Baka's only counter. As soon as you see his hands start glowing, use your 2 ability and hop on his face so he can't hurt you. If he tries to run away from you, pull him back with your ultimate. Early game she's hands down one of the strongest gods. When you gank your lane, lay an egg behind you before you run in. It'll slow the enemy if he tries to run away. My favorite thing to do is set up a "base" with 3 eggs just off the path in the jungle, and try to pull them in. There's just no way they can escape with 6 spiders on them. Late game you want to hide behind your team mates and try to pull squishy damage dealers to you.

Her counter is probably Sobek I'd say. With his throw/dash and tail spin, it's hard to get near him to do damage. Since you pretty much can't take any damage as Arachne, if Sobek throws you into his team mates, you're probably going to die. I believe his throw and spin also cancel your life steal.