Portal Defense: How to Manage Dice Summons and Board Merges

To prevent grid lock and keep pace with incoming waves in Portal Defense, merge matching towers immediately to open up grid tiles, and pause random dice rolls when high-density or boss waves approach to spend gold on upgrading existing units instead.

Controlling Grid Placement and Tower Merging

Board space is your strictest bottleneck. Random dice rolls cost gold and place towers onto open grid tiles. If your board fills up with low-tier units, you will be unable to place new defensive structures during critical moments.

Maintain grid efficiency by organizing towers according to these rules:

• Frontline Anchors: Place your strongest single-target and splash-damage towers on the tiles closest to portal exits to eliminate incoming enemies immediately upon spawn.
• Center Buffer: Leave central tiles open to place utility towers or high-tier units that provide global benefits in the mid-game.
• Immediate Merges: Combine two identical units as soon as they appear on your board. Merging opens a tile while increasing overall unit power without expanding your board footprint.

Balancing Gold Rolls and Unit Upgrades

Relying entirely on random rolls quickly drains your gold reserve without guaranteeing useful units. Monitor the wave counter at the top of your screen to decide whether to roll for new units or improve your current roster.

A single upgraded high-tier tower holding a chokepoint provides more defensive power than several low-level towers scattered across the board. If your defense begins to struggle, focus your gold into upgrading existing anchor towers rather than gambling on new random rolls.