I love that you also made a tower defense! Core gameplay loop is fun, but it doesn't feel well balanced. It feels like there are multiple enemy types (or the scaling is indistinguishable) with different HP but I can't tell them apart. With that in mind the trap (e3) is rather expensive for a one time use.
The poison damage is also interesting as it forces you to place towers in the front rather than at choke points (except for the e2 towers obv), but enemies are way too fast that it would matter.
With a simple 4 directional TD like this I could also imagine the towers being placed automatically facing the direction of the closest path with the option to manually adjust afterwards.
The standard tower could also be uniquely useful if it shot a piercing projectile, so it'd be much better at corners (which was my first thought).
There's obviously lots of potential here and lots to improve. I could expand on this list on and on. Let me know if you're even interested :)