Hey, really cool game!
Agree with other comments, a bit hard at start, and would be nice to have some indication to where the obelisks are, because I spent the first half of the game only trying to survive. I would also make the portal stand to more than just a single hit, or make the towers a bit stronger, I didn't manage to protect the portal and I played for like 30 min.
I have a similar game, and I'd love to hear your opinion https://beorgames.itch.io/hero-battle-fantasy-arena
Cheers!