The game follows the movie's storyline with Flik as the player character, featuring fifteen levels with every third being a boss stage. The central gimmick is growing plants; Flik can carry and plant large seeds to produce various plants that help him progress, and he can collect tokens that grant him new colors to turn seeds into and new plants to produce from each seed color. Each level has a main goal to reach (most of them being to reach an exit, though some require collecting items or finding characters) as well as three Success Tokens that can be collected through completing other tasks.
Traveller's Tales would later develop Toy Story 2: Buzz Lightyear to the Rescue!, another Pixar 3D platformer that shares some traits with A Bug's Life but is otherwise a more traditional collectathon.
Tropes featured in the game:
- Abnormal Ammo: In the final level, Hopper attacks by throwing platinum berries at Flik.
- Adaptational Badass: Flik actually fights in this game. To give a comparison, in the movie, he was beaten to a pulp by Thumper. In this game, he kills Thumper—in the third level, no less!
- Adaptational Jerkass: Okay, Thud was already a jerk in the film, but he and the other flies were merely Bit-Part Bad Guys who wanted to beat up Francis and the other circus bugs out of revenge. In this game, he's a full-on boss who tries to outright murder Flik for seemingly no reason.
- Adaptational Nice Guy: Mr. Soil is among the ants who look down on Flik in the movie. This game has him as the latter's mentor who gives him instructions in the tutorials.
- Adaptational Villainy: Molt was an Affably Evil Punch-Clock Villain in the film who never personally antagonized the ants and eventually performed a Heel–Face Turn. Here, he fights Flik and is killed by him.
- Advancing Boss of Doom: Hopper chases after Atta and Flik in "Atta Flight", hurting them if they move too slowly through the riverbed.
- Airborne Mook: Flies, wasps, and mosquitoes; flies are smaller and more damage-absorbing while always remaining in flight, mosquitoes are larger but not as tough and sometimes drop to the ground, and wasps always remain airborne but can do a Ground Pound move to sting Flik.
- Alternate Monochrome Version: The Game Boy Color version is one of the black cartridges, meaning it has an alternate monochrome palette to make it backwards compatible with the original Game Boy and the Super Game Boy accessory for the Super Nintendo Entertainment System.
- Annoying Video Game Helper: Invoked with the ants in "Lead the Revolt". They try to help Flik by throwing him red berry pickups... which is a bad thing, because Molt only takes damage from blue berries and above. If Flik touches a red berry that the ants throw to him, then he's left with a useless weapon until he grabs a stronger berry pickup.
- Artistic License – Biology: The daddy longlegs enemies periodically attack by launching webs, despite seemingly being based on the harvestman, which is not a spider.
- Ascended Extra: In the movie, Thud was a side character who never even met Flik. Here, he's a boss.
- Awesome, but Impractical: Flik's Harvester appears in several levels, and while operating it, he's invincible to enemy attacks, magnetizes grain towards him, and permanently kills any enemy that he kills with the blades (in one hit no less). However, Flik moves very slowly while using it and can't jump without dropping it, and only enemies that can be killed by red berries are affected by its blades. Since the Harvester is never required to finish a level, it's best to ignore it and use gold berries to kill the enemies instead (unless you don't have them yet).
- Big Creepy-Crawlies: All of the enemies besides the bird are insects, worms, and spiders, though they only appear large because Flik is also an insect.
- Bonus Level: There are three secret levels that take place in the circus bugs' tent, all sharing the same layout but containing different items and a different goal. To access them, Flik needs to perform a hidden action five times in a row (such as bouncing on five different mushrooms) that will warp him from the current stage to the bonus level. Collecting the exclamation point in each one unlocks a movie clip.
- Boss Banter: Molt and Hopper, the only two bosses who can speak.
- Carnivore Confusion: Rosie is still an ally, but other spiders and Daddy Long Legs' appear as enemies. It's even more confusing because in the cutscene that introduces the player to the city level has the shot of the Daddy Long Legs from the movie passing over Flik and making no attempt to harm him or any other insects in the area, whereas the very first enemy in the level is a much more aggressive Daddy Long Legs, leaving it ultimately to individual cases.
- Color-Coded for Your Convenience:
- The various plants are coded by seed color: brown seeds grow plants that give Flik an aerial boost, green seeds create progressive taller leaf platforms, blue seeds produce buds that spit out pickups, purple seeds spawn berry pickups, and yellow seeds grow into attack plants.
- The berries are colored by strength: red berries are weak, blue ones are stronger and produce smoke, green berries home in on enemies, purple berries have homing and are even stronger, and gold berries don't home in but prevent enemies from respawning after death.
- Cowardly Boss:
- Thud flies from one side of the rolling tin can to the other every time he takes damage, dropping several pieces of grain and a healing leaf each time.
- Hopper flees when he's hit with a berry in the final level, eventually causing him to knock over barricades that block off parts of the level. The goal is to corner him at the top of the cliffside where the bird's nest is, as the remainder of his health can be drained from there.
- The bird itself becomes this in its boss level if you get the gold berry, flying high up to avoid you.
- Cut and Paste Environments: Anthill and Anthill Part 2 take place in the same location (the area surrounding the anthill). The Molt boss battle takes place in a small section of this area.
- Death by Adaptation: In this game, Thumper, Thud, and Molt are all fought as bosses and killed by Flik.
- Demoted to Extra: P.T. Flea, who appears in the movie clips but never shows up in gameplay unlike all the other named characters.
- Distressed Damsel: The goal of the "Ant Hill, Part 2" level involves having to rescue a captured Atta from Hopper.
- Edible Ammunition: Flik can throw berries to hurt enemies, with the color of the berry determining its strength and properties.
- Flunky Boss: Most bosses aside from Thud are this such as Thumper who has two mosquitoes and Hopper who has fifteen grasshoppers.
- Game-Over Man: A repurposed clip from the film featuring Hopper (the "You think this is a game?" scene) is played after you lose your last life, before the game over screen appears and the game resets. It works very well because Hopper is staring right at the camera in said scene.Hopper: Have you been playing all summer?! You think this is a game?!Atta: No, no, please!Hopper: Well, guess what?! You just lost.
- Gold-Colored Superiority: Gold berries are the strongest projectiles in the game and the only kind that can kill enemies permanently.
- The Goomba: Spiders are the first enemy you see, the most common, and the second weakest, only hurting Flik if they touch him and dying in one hit from a jump or two hits from a berry throw.
- Gotta Catch Them All: There are 48 Success Tokens spread across the fifteen levels plus the tutorial, and collecting them all requires collecting smaller items as well.
- Ground Pound: Pressing the jump button while Flik is in midair makes him perform a butt-stomp, killing any enemies he lands near. It also slightly stalls his decent, which can be exploited for long jumps. The wasps can also "butt-stomp" Flik if they get above him (i.e. sting him).
- Guide Dang It!: The game never hints at the existence of the secret bonus levels, with the only indication that they exist being the exclamation points produced when you do the actions related to their unlock conditions. The unlock methods (bouncing on five mushrooms in a row, killing five enemies by squashing them flat without missing, and killing five grasshoppers in a row without missing any berry throws) are hard to do by accident and can only be done in a few select levels each.
- Invincibility Power-Up: The base-level plant of the blue seed spits out shiny nectar that briefly turns Flik invincible. It's mostly situational, but it comes in handy for crossing the toxic puddles in "Little Ant, Big City". The Harvester also makes Flik invincible as long as he uses it.
- King Mook: Molt shares the same movement behavior as the grasshopper enemies (patrolling a small area and charging at Flik if he enters that area) while having a much larger health bar, faster movement compared to other grasshoppers, and the level's gimmick of having the ants throw red berries that take the place of your current berry. Hopper and Thumper averts this by being the only grasshoppers than can fly and throw projectiles.
- Kung Fu-Proof Mook: All grasshoppers, including bosses, are immune to red berries, requiring Flik to grab a stronger type of berry to hurt them. Some other enemies also resist red berries, but usually can be killed with a ground pound.
- Land Mine Goes "Click!": The final plant upgrade for the yellow seed produces a land mine flower, which explodes when an enemy goes near it or when it's thrown. It can only be grown in "Grasshoppers Leave" (and the third bonus level), but it's the only way to permanently defeat enemies for the Enemy Token since the level contains no gold berry pickups.
- Last Lousy Point: Collecting all three tokens in a level unlocks a bonus movie clip, and 100% Completion unlocks one more movie clip as an award... so why are there still three locked spaces in the clips menu after collecting everything? They're locked behind the three circus bonus levels, which can be accessed by performing specific actions within other levels.
- Leaning on the Fourth Wall: The game's Game Over sequence has some fun with changing one of Hopper's scenes into a jab at the player, rather than the ants as it was in the film:Hopper: "Have you been playing all summer? You think this is a game? Well, guess what? You just lost!"
- Macro Zone: The entire game takes place in one, since it's from an ant's perspective.
- Metropolis Level: The City Entrance and City Square levels take place in the insect city, where Flik is tasked with locating all the circus bugs.
- Missing Secret: Each seed color has four different plants that it can grow into... except for the yellow seed, which only has three. None of the levels in the game contain enough yellow seed tokens to upgrade it another time, and the Bonus Level that features every plant proves that there are only three yellow seed plants.
- Poison Mushroom: Berry pickups are not sequenced, so a stronger one can be replaced by a weaker one if you collect it. The boss fights against Thud and Molt exploit this by throwing out low-tier berry pickups as an obstacle.
- Power-Up Magnet: While Flik is moving a Harvester, any nearby grain flies towards him.
- Pre-Rendered Graphics: The cutscenes are clips from the movie.
- Remixed Level: One of the last stages of the game is "Grasshoppers Leave" (outright called "Anthill, Part 2" on the level select menu), which takes the first non-tutorial level of the game, "Welcome to Ant Island", and overhauls it; most of the enemies have been replaced by grasshoppers (which need to be killed with yellow seed plants, since the game doesn't give you any berry upgrades), all the collectibles are found in different places, and the level goal is changed from entering the anthill to finding a way to attack Hopper and make him drop Atta. It's also pouring rain as opposed to being sunny, though this only affects the visuals.
- Respawning Enemies: All enemies will respawn indefinitely after they're killed, but there are three ways to prevent them from returning: hitting them with gold berries, chopping them up with the Harvester, or blowing them up with the mine plants produced by a max-level yellow seed. Defeating all the enemies in a level through these methods awards you with the Enemy Token for the level. Notably, even the bosses have to be killed with the golden berry or else they won't count toward this, despite the fact that they stay dead no matter how you kill them. This is a problem during Thud's boss fight, because if you get hit by one of the blue berries he throws at you after you have picked up the golden berry, instead of damaging you, the blue berry will replace the golden berry as your weapon with no way to get the golden berry back.
- Notably, how the enemies respawn varies depending on their type. Spiders, flies, beetles, and some other enemies will pop out of the ground. Grasshoppers, mosquitos, and wasps will fly in from above. Daddy Long Legs' will just spontaneously materialize where you killed the previous one.
- Shout-Out:
- To Bambi: Thumper's boss level is titled "They call him Thumper", and Flik's first quote upon seeing Thumper is "I'm psycho, that's why they call me Thumper".
- When Flik encounters a mosquito in Riverbed Canyon, he may comment "Mosquitoes. Why'd it have to be mosquitoes?"
- When Flik picks up an invincibility powerup he will shout "I AM INVINCIBLE!"
- Sound of No Damage: Hitting an enemy that resists red berries, such as a grasshopper, with a red berry will produce a "boink" sound as opposed to the blasting sound effect that plays when the berry actually does damage.
- Spelling Bonus: Each level contains collectibles of the letters F, L, I, and K. Collecting all four letters gives you the FLIK Token for that level and an extra life (the only way to gain extra lives in the game. However, it maxes out at 10).
- Spiders Are Scary: Spiders and Daddy Long Legs' appear as enemies, even though Rosie is still an ally.
- Springy Spores: The base level of the brown seed produces a mushroom that works as a bouncy platform, though the boost it gives is very small.
- Trampoline Tummy: In level 10, Heimlich himself functions as a bouncy platform, much like the aforementioned mushrooms, you can use to reach a higher ledge. He even comments that it tickles when you bounce on him.
- Unexpected Gameplay Change: In "Atta Flight", you control Atta as she carries Flik through the riverbed while fleeing from Hopper changing the game into an auto-runner; Atta moves forward automatically and can fly by holding the jump button, while Flik can still throw berries as normal. This is one of two levels in the game that doesn't allow you to grab and plant seeds (the other, "Horsefly Mayhem", plays like normal and just doesn't contain any seeds to use).
- Wake-Up Call Boss: Thud. After Thumper and
the bird, he is the first boss to truly challenge the player. - Warm-Up Boss: Thumper is the first boss of the game, and he mostly sticks to the center of the level so you can ignore him and grab stronger berries, which can be spammed to defeat him in seconds. Every other boss either incorporates more platforming or has better means of hurting Flik apart from the bird.
- A Winner Is You: Your reward for beating the game? A screen with Flik that says "Congratulations! Game Complete"
