I feel like this review is going to come across as overly negative (And probably overly long as well, sorry) so let me start out with what I liked.
I love that io 2022 we have a sequel to Portal Defenders. I remember obsessively playing the first one back in the day, trying to beat it for the first time, so this was like a nice hit of nostalgia. As with the first game, I love the theme-ing of this project, portal defenders makes sense as a tower defense game. And with that, I love the art style and music as well. I see a lot of potential for this game, or maybe even a sequel with all the shit Im about to suggest.
I'll transition into my negative portion by saying this. This kind of feels like a game that would have won Pico Day in like 2012. I feel like as a tower defense game its alright, but it feels al little dated and there's a lot to be desired in terms of features. The tldr of this section is Im just going to point at Kingdom Rush and say "Do that" as its probably the best flash Tower defense game Ive played. And I feel like a lot of its features could be borrowed to improve this game.
For example, I hate that I don't know which path the next wave is coming from. Its really only an annoyance in the first wave, and in all actuality its kind of a minor one, but its something that happens on every level. I start the mission, instantly click the whistle just to see what lane they are coming from, then back out to the map screen and restart the mission to properly build my first few towers. Those first few steps could be avoided if there was just an arrow or some indication as to the spawning point. Also in relation to this, some way to restart without backing out to the world map would help save a few seconds as well.
I also feel like the game isn't balanced all that well. For the most part i found it way too easy. The hardest part of any level is maybe the first two waves, when you're not sure what's coming. After that its usually a cake walk, with a few exceptions. After you establish a few towers, you're almost never in any parrel. I never felt like I was hurting for grounds gold, and I was able to call most waves in early. For some stages, I didn't even need to call in the Mr. Snips power. Or use all the build zones for some stages. I think I 5 starred each level on my first or second attempt. Its a far cry from the first portal defenders, where it felt like a challenge.
The tower selection itself seems very limited as well. I didn't really have to think all that much about upgrading, just pour money into one of the stats until you max out. And the laser turret is probably the most over powered one, especially when maxed out. They shred through most enemies, to the point where I don't even really need the area of effect canons, notably in the final few levels when the vans come out. The cannons are far to slow to be effective against them unless they stop, Which they do so sporadically you might as well not even bother. And since they tear through you soldiers, the best strategy is just build nothing but laser towers and max them out, which gets pretty boring.
All in all, the vans kind of kill the last few levels for me. The only time I lost was when they just show up, tear through my defenses and bomb the shit out of me, in a way that feels a little cheap. And like I said, they make 2 of the 3 tower types basically useless. Its also kind of annoying that they can heal from the med bags the blimps drop.
But in general the enemy variation isn't that great either. I never felt like I needed to adapt to anything besides building more towers. It seems like they are all just fast a weak or slow and take more damage. This could be solved by adding more specialized enemies that are weaker against certain kinds of towers, and upgrade paths for the towers that make them better at taking out certain kinds of enemies.
Also, unrelated to anything Ive said, and as much as i love the dulcet tones of Johnny Utah, the tankmen quotes get old after a couple of stages.
Again, I apologize for the length and nitpickyness of the this review. But I see a lot of potential fora great game. I know its easy for me as an outsider to bitch and complain, even when its better than anything I could create myself. Im a fan of anything newgrounds, and i hope this isnt the last we see of portal defenders!