Flag of Power is a new King of the Hill-inspired game mode in the Backyard Battleground and is located in the direct center of the map. The player, playing as a plant or zombie, can raise the flag in the middle of the map. Once the player raises the flag, their damage will be tripled and their resistance to damage will be four times higher. A large ring will appear around the flag, and the player must stay in the ring to ensure the flag stays up, as if they leave and an opponent is in the ring, the flag will start to lower. Four plant pots or Build-a-Bot stations will also appear to help the player protect the flag.
Crazy Dave or Dr. Zomboss (depending on which side the player is on) will unleash waves of AI foes, from normal AI, AI heroes, Al champions to Al bosses. In the middle of each wave, a reinforcement crate will be dropped in a random place on the battleground, and the player can break it to either get AI helpers or coins. After each wave, the player will be rewarded with lots of coins. After Crazy Dave or Dr. Zomboss has unleashed the last wave (a boss wave), they will start an endless mode, and an endless amount of AI foes will appear, from regular AI to AI bosses, just to see how long the player can hold the flag. If the opposite side manage to take down the flag by staying in the circle for a long time without a player or one of their allies from the reinforcement crates, the game will end, and all bosses and enemies created by the Flag of Power will instantly be vanquished.
This mode is not actually unlocked from the start of the game; the player must complete the Dave-bot 3000 mission "Flag of Power."
List of waves
- Weed Attack! (Well done minions, that flag makes us INVINCIBLE!) (That flag reminds me of my pants...)
- Sunflower Attack! (My SUNFLOWERS will brighten your day!)
- Peashooter Attack! (My PEASHOOTERS are ready!)
- Cactus Attack! (I need your help, CACTI!)
- Chomper Attack! (This calls for my CHOMPERS!)
- Rose Attack! (My ROSES are in bloom!)
- Corn Attack! (I heard zombies love CORN!)
- Citron Attack! (Roll out, CITRONS!)
- Boss Attack! (I used extra fertilizer on these guys!)
- Endless Attack! (Those were my favourites... Good thing I've got an ENDLESS supply!)
- Browncoat Attack! (Flag of Unimaginable Power... ACTIVATE!) (Flag of Unimaginable Power? WE MUST STOP THEM!)
- Pirate Attack! (My PIRATE zombies will end you!)
- Science Attack! (SCIENCE will be your DOWNFALL!)
- Engineer Attack! (My ENGINEERS will be your destruction!)
- All-Star Attack! (ALL-STARS... get them!)
- Soldier Attack! (Unleash the SOLDIERS!)
- Super Attack! (Time to shine, SUPER BRAINZ!)
- Imp Attack! (Send out the IMPS!)
- Boss Attack! (That's it! Time for a BOSS WAVE!)
- Endless Attack! (Fine... whatever... I give up... JUST KIDDING! INSANE ENDLESS MODE!)
- Main article: Flag of Power/Strategies
- For an unknown reason, Rose gets an x16 damage boost when raising the flag in the beta.
- This and Infinity Time are the only endless modes, and therefore, the player cannot actually "win".
- According to Dave-bot 3000, the Flag of Power is made by Crazy Dave.
- Crazy Dave says that he made it out of a pair of his old pants.
- For an unknown reason, Baron Von Bats and Zen Sensei do not appear in the Flag of Power in the full game.
- In the beta, the Endless Attack was titled "???".