33RD is a unique "Random Defense" mobile game. Not only the aesthetics here are unusual, but the gameplay itself is also far from standard.
The first thing you'll probably notice is the looks of characters/towers. Pixel-art animals with guns might be heavily simplified, but they are recognizable enough, even with more than 10 summoned creatures. Additionally, it's just fun to watch tiny penguins of hamsters pointing their massive guns. Apart from the zoo (and one central "mage" character there's not much to see - just simple, 2d board/UI mixed with some pixel-art items.
The gameplay differs in several aspects from the typical random defense title. The first thing is placement & distance - here, the board is split into 8 2x2 mini-boards, lying around hour hero. That makes place for using a range of towers - not every animal can shoot every monster on board, adding another component to tactical equations. Also, winning/losing is not as simple as letting a monster cross point X. Here, if you're not able to kill some slime, it'll go to the enemy's board. If it's killed there, it will turn into a missile targeting you. And another winning condition is just getting 200 kills before your opponent.
33RD lets you play the usual co-op and duel modes (with randoms or your friends using code), but there's also a solo campaign. It can be used just to get more gold, to acquire new animals, or upgrade existing ones.
Aside from those standard tower management, this game lets you upgrade your mage character and even craft gear for her, providing special in-game bonuses.
Getting gold and animal shards is crucial here, and your main options are a premium shop or just playing. Reward ads won't help you much there, not to mention the lack of forced videos.