Portal Defense: Chapter 2-16 Central Hub Defense Guide

To beat Chapter 2-16 in Portal Defense, build your main kill zone at the central intersection where all portal paths converge rather than placing towers along the outer edges of individual lanes. Because enemies emerge from multiple portals simultaneously, outer towers waste range and gold on empty paths. Concentrating your high-range and area-of-effect (AoE) units in the middle ensures consistent coverage across every incoming wave.

Centralized Tower Placement Strategy

Positioning your towers at the central junction maximizes damage uptime and prevents fast units from slipping through unhit. Place your long-range towers in the innermost central tiles so their attack Radii cover every intersecting path.

Structure your central hub using a layered defensive lineup:

Front-Line Crowd Control: Place cold or slowing towers at the entry point of the central intersection to group enemies together as they enter the kill zone.
Central AoE Damage: Position fire or explosive towers directly behind your crowd control units to inflict heavy area damage on clustered enemy groups.
Base-Exit Cleanup: Keep a small reserve of high-attack-speed, single-target towers near your core exit to finish off fast units that survive the central barrage.
Portal Entrance Buffers: Place low-cost, low-tier towers at the mouth of each outer portal to disrupt enemy movement early, but do not invest upgrade gold into these outer spots.

Resource Allocation and Upgrades

Gold efficiency determines success in the later waves of Chapter 2-16. Upgrading a single tower to its maximum tier early limits your coverage across multiple lanes.

Establish a broad foundation: Fill the central intersection with un-upgraded or low-tier towers to cover all incoming paths before spending heavily on tier upgrades.
Upgrade central units first: Focus high-tier upgrades strictly on innermost towers that touch multiple lanes.
Bank gold during easy waves: If your central setup clears waves quickly without leakage, save your income during wave transitions. Holding gold lets you adapt your late-game tower elements to match incoming enemy armor types.