This is an adaptation of a comment I left for the Cane and Rinse podcast.
Plants vs. Zombies (2009) is very likely the most widely adored Tower Defence game of all time, at the very least it is certainly the most decorated. The game was a surprising phenomenon for a genre that had typically been viewed as web browser fodder. Yes, the game is mechanically simple when compared to similar titles released before and after it. But it’s unfair to assume that Plants vs. Zombies is only well liked because it’s approachable by the mainstream. Plants vs. Zombies actually fixes one of the major flaws in almost all tower defence games by being explicitly simple in how it relays information to the player.
For comparison sake think of any traditional Tower Defence game, games like Desktop Tower Defense (2007) or PixelJunk Monsters(2007). So many of these games have a terrible time relaying to the player what exact gameplay choices were correct/beneficial and which were mistakes. These games have many mechanical systems twisted together very tightly and it’s very hard for the player to isolate them in their mind. A level can be failed through poor economy management, poor time management, poor unit placement or poor unit choice just to name a few. As these systems are tied so tightly it’s often impossible to figure out where the player went wrong. Too often a player will misidentify where they failed and mistake which specific choice failed them. The player is almost always taking away the wrong lessons from a specific round of a tower defence game, they merely progress through the early game based on its ease. This will inevitably lead to an eventual challenge the player can’t overcome, and they won’t have the tools to evaluate what they should be doing differently. Most players won’t want to blindly experiment and it’s here they’ll bounce off the game. Too many mechanics wound too tightly.
Plants vs. Zombies on the other hand makes it abundantly clear to the player what works and what doesn’t. As the game space is split into five very segmented lanes the player is almost playing 5 entirely separate games at once. If the player’s top lane consisting of chompers is overrun while the lane of snow peas is not, the player instantly understands what kind of mistake they made. Plus the game usually chooses not to hide information like time remaining until the next big wave, or even which zombies will constitute that wave. The game provides the player the information they need to make strategic decisions, which makes the decisions rewarding even if they were easy.
Plants vs. Zombies sequesters its game space and its mechanics to make a game that is legible, and thus enjoyable. Sure this makes Plants vs. Zombies significantly easier than other tower defence games. But this trade-off totally sheds the obtuseness typical of its peers, and makes a game that is never unfair. Popcap is smart to offer so many side modes, game types, puzzles and mutators to keep the game from getting stale, as it does essentially tell you how to beat it.