The Super-Block Meter is a gameplay mechanic in Plants vs. Zombies Heroes. At every attack, the Super-Block Meter charges, and when it is fully charged, the attack is blocked, and the player receives one random superpower from their superpower set. The superpower can be played immediately for free, or turned into a 1-sun/brain card, depending on the side they are on, to be played at a later turn. The Super-Block Meter only works properly if there is space on the player's hand for a superpower. Therefore, if the player has 10 cards or more in their hand, and their Super-Block Meter is full, the Super-Block Meter will fail to block attacks until the player plays some of their cards.
After every hit, there is an equal chance of charging one, two or three bars of the Super-Block Meter, out of 8 bars total. The player can only block three times before the Super-Block Meter is destroyed, and the only way to attack the opposing hero without charging the meter is via fighters with the Bullseye trait.
- Mechanic change: Charges based on percentages; randomly fills mini, normal, or double amount. 5% chance to "mega charge" and block instantly. → Charges based on segments, with 10 needed to block. May fill 1, 2, or 3 segments, or "Insta-Block" instead.
- Mechanic change: Removed Insta-Blocks from occurring naturally.
- Segment change: 10 segments → 8 segments
- ▲ Mechanic change: Only blocks damage that activates it. → Blocks all incoming damage once activated.
The Super-Block Meter is a luck-based mechanic, and should not be relied to win games or save yourself from defeating blows. There is no specific strategy or tip either, since there is almost no way to control how the Super-Block Meter works except for the best. The best you can do is attempt to charge the Super-Block Meter in your favor. If there is a low-strength fighter on the field like an Imp or a Peashooter, it is usually preferable let them attack you in order to fill the Super-Block Meter at a minimal health cost, and furthermore, to have a higher chance of blocking an attack from a more powerful fighter, which may be the key to victory. For example, abilities that take effect instantly like Grapes of Wrath and Dandy Lion King's have a higher chance to be blocked by timing the Super-Block Meter well.
The only way to completely counter this mechanic is with the Bullseye trait, especially Shieldcrusher Viking, who drains the entire meter with each direct attack. However, Bullseye decks are not easily viable in the current meta due to their slow tempo.
—Devin Low, Creative Director and Lead Designer, Plants vs. Zombies Heroes
Insta-Blocks (called Mega Charges prior to version 1.4.14) were a mechanic that existed in older versions of Plants vs. Zombies Heroes. In those versions, the player had a 5% chance of receiving an Insta-Block whenever struck by a non-Bullseye attack, which would completely fill the block meter immediately regardless of any previous charge. It was removed on update 1.6.27, as PopCap decided that the mechanic introduced an unnecessary layer of luck to the game, created too many unfair situations, and made the block meter more critically rated.
For a time after their removal, due to a glitch, Insta-Blocks could still be triggered after a Soul Patch was played, or when a plant with Bullseye and a plant without Bullseye attacked in the same lane. It is unknown how exactly the glitch worked on a technical level. However, this has since been fixed.
- So far, Shieldcrusher Viking is the only card that can completely empty the Super-Block Meter. This excludes various bugs and glitches.
- Sometimes, the Super-Block Meter may stay full, but not negate damage. This usually happens with cards that have abilities that can damage the opposing hero like Sergeant Strongberry or Punish-Shroom. This may also happen if a player wins or loses a battle when these loops occur.
- A wall of leaves appears when the plant hero does a Super-Block, while a line of gravestones appears in the zombie hero's case.