# Portal Tower > The Portal in Blockade Brigade: 475 gold, sends up to 5 ground enemies back down the path. Distance, Power, levels, research and FAQ. - Page: https://blockadebrigade.com/towers/portal - Site: Blockade Brigade, a tower defense game for Windows PC (https://blockadebrigade.com/) - Last updated: 2026-10-23 - Text generated: 2026-11-02 06:40 UTC [Utility Tower](https://blockadebrigade.com/towers/utility) ## Portal Tower Sends enemies back along the path, picked by its target priority 475 gold, Ground only, Research 175000 The Portal does not shoot. Every 8 seconds at level 1 it opens portals under the ground enemies in its range and drops them back down the path, so they have to walk past your other towers again. It grabs 1 enemy at a time at level 1 and up to 5 at level 10, and sends them 4 tiles back at level 1, up to 8.5 at level 10. Strong enemies resist its Power and go a shorter way, never less than 20% of the full distance. It costs 475 gold and cannot move anything that flies. Build your own Portal ### Attributes Level 1, on the ground Cost 475 gold to build Unlock 175,000 XP XP to research it (main menu, Upgrades & Research) Sell value 356 gold 75% of the gold spent on it; all of it back within 15 seconds of placing Can hit Ground Power 200 Openings 0.12/s Range 6 3 tiles Targets at once 1 grabbed a shot Power uses 20 when firing · 1 on standby Full power only while it has a target. Switch it off to free its power. Neighbours +15% damage, +10% fire rate each Same-type towers on its four sides, up to four (+60% / +40%). Connected Portals need 25% less power. Platforms +8% damage, +0.5 range a level of height Small +1, Medium +2, Large +3, up to 3 stacked. Hills up to 15 (above 5 is rare). Ground Grass: −5% damage No penalty on rock, or on a platform (it stands on steel, even over grass) Level parts Base: 1 green level light, plate 01 Research 3 items, 5 levels each 250 / 750 / 2,000 / 6,000 / 15,000 XP a level, 72,000 XP for all. Power, Quick Recharge, Long Reach Cards Damage, Fire Rate, Range End-of-wave cards: up to 5 of each a game, then Endless cards Base numbers: no research, cards or neighbours. (+n) is the change from the level before. ### How to use it #### Late on the path An enemy sent back walks past every tower behind it again. Near the end of the path that is your whole defence; near the entrance there is little path behind it, and an enemy is never sent back past the start. #### Power decides the distance An enemy whose health, armour and shield add up to no more than the Portal's Power goes the full distance. A stronger one goes Power / strength of it, never less than 20%. Power is 200 at level 1 and 920 at level 10. #### Pick who goes Its target priority chooses the enemies it grabs. First sends back the enemy closest to your base; Strongest spends the portal on the big ones, which go a shorter way. #### Hold them in range It recharges slowly, so a Cold Snap or a Gravity Well nearby keeps enemies inside its range until the next portal opens. #### Build in rows, go high Each Portal on the four sides of another gives it +15% Power and +10% recharge speed (up to +60% and +40%). Each level of hill or platform gives +8% Power and +0.5 range; on bare grass it loses 5% Power, unless it stands on a platform. ### Build it Pick a level, research, end-of-wave cards and where it stands, and see what your Portal ends up doing, worked out the way the game does it: its Power, how often it opens, how many enemies it grabs and how far they go. Share the build with a link. How the configurer works it out (formula, card values, share-link format) #### How the game adds it up - **Damage:** level base x (1 + neighbours x 0.15) x (1 + height x 0.08) x ground (0.95 on bare grass, else 1) x (1 + research %) x (1 + cards % + Endless %) - **Fire rate:** level base x (1 + neighbours x 0.1) x (1 + research %) x (1 + cards % + Endless %) - **Range:** level base + height x 0.5 + level base x (research % + cards % + Endless %) - **Dps:** damage x fire rate, one hit on one target, before splash, afflictions and armour - **Rule:** Every source multiplies damage and fire rate; cards and Endless cards of one stat add into one percent. Range percents are all of the levelled base, added. #### End-of-wave cards Each wave offers 3 cards. Up to 5 cards of each stat a game, then that stat comes only as grey Endless cards (a random amount in the range shown). Percent per card: | Card | Normal | Common | Rare | Epic | Legendary | Mythical | Endless | | --- | --- | --- | --- | --- | --- | --- | --- | | Damage | 2% | 5% | 10% | 15% | 25% | 35% | 1-5% | | Fire Rate | 2% | 5% | 10% | 15% | 25% | 35% | 1-5% | | Range | 2% | 5% | 10% | 15% | 25% | 35% | 1-5% | #### Research Unlock: 175,000 XP; its upgrades: 72,000 XP for all. - **Portal Power:** +10% a level, 5 levels (+50%), 250, 750, 2,000, 6,000, 15,000 XP - **Quick Recharge:** +6% a level, 5 levels (+30%), 250, 750, 2,000, 6,000, 15,000 XP - **Long Reach:** +6% a level, 5 levels (+30%), 250, 750, 2,000, 6,000, 15,000 XP #### Where it stands - Each same-type neighbour on its four sides: +15% damage, +10% fire rate (up to 4). - Each level of height (hill + platforms): +8% damage, +0.5 range. - Bare grass: damage x0.95 (no penalty on rock, or on a platform: it stands on steel, even over grass). One tile is 2 range units. #### This tower's own rule - Each opening grabs up to 1, 1, 2, 2, 3, 3, 4, 4, 5, 5 ground enemies (levels 1 up) and sends them back 4, 4.5, 5, 5.5, 6, 6.5, 7, 7.5, 8, 8.5 tiles along the path; an enemy stronger than the Portal's power goes power / strength of that, never under 20%. Each lands with a hit of 25% of the power and cannot be grabbed again for 6 s. Recharge = 1 / fire rate. #### Worked examples - [`#build:l10~r.damage.5~c.damage.55555~e.damage.5x10`](https://blockadebrigade.com/towers/portal#build:l10~r.damage.5~c.damage.55555~e.damage.5x10): damage 4485, fire rate 0.161/s, DPS 722, range 8.25. - [`#build:l10~r.damage.5~c.damage.55555~e.damage.5x10~n3~h15`](https://blockadebrigade.com/towers/portal#build:l10~r.damage.5~c.damage.55555~e.damage.5x10~n3~h15): damage 14307.1, fire rate 0.209/s, DPS 2,994, range 15.75. #### Share-link format A build is the page address + `#build:` + parts joined by `~`, in any order; parts left out are 0 / none. Opening the link loads the build and scrolls here. Links shared from the page also carry `?utm_source=...&utm_medium=...&utm_campaign=tower_build&utm_content=...` before the hash; they are optional. - `l`: tower level 1..10 - `r..`: research level 0..5 of a research item (damage, fire_rate, range_radius) - `c..`: end-of-wave cards of one stat, one digit per card = its rarity (0 Normal, 1 Common, 2 Rare, 3 Epic, 4 Legendary, 5 Mythical); at most 5 a stat - `e..x`: Endless cards of one stat: count cards of +amount% (only once that stat has 5 cards) - `n`: same-type neighbours touching it, 0..4 - `h`: height: hill + platform levels, 0..15 - `g`: standing on bare grass (no platform) - `s`: level of the Cold Snap over it, 0 = none (1..10) - `sp0`: that Cold Snap has no power (it cools nothing) - `w`: water tiles beside it, 0..4 (sides not taken by neighbours) - `k`: towers in its connected chain, itself included (at least neighbours + 1) - `kw`: water tiles beside the whole chain ### Every level Base numbers: no research, cards, height, neighbours or tower XP. Power decides how far strong enemies go and the hit they take when they land; the full distance is for enemies no stronger than its Power. Tower XP levels count as extra levels for grabs and distance. | Level | Upgrade | Total spent | Power | Openings | Range | Grabs | Sends back | Strong sent back | Again after | Power | | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | | 1 | build 475 | 475 | 200 | 0.12/s | 6 | 1 | 8 | 1.6 | 6.0s | 20 | | 2 | 760 | 1,235 | 280 | 0.13/s | 6.25 | 1 | 9 | 1.8 | 6.0s | 24 | | 3 | 1,216 | 2,451 | 360 | 0.13/s | 6.5 | 2 | 10 | 2 | 6.0s | 28 | | 4 | 1,945 | 4,396 | 440 | 0.14/s | 6.75 | 2 | 11 | 2.2 | 6.0s | 32 | | 5 | 3,112 | 7,508 | 520 | 0.14/s | 7 | 3 | 12 | 2.4 | 6.0s | 36 | | 6 | 4,980 | 12,488 | 600 | 0.14/s | 7.25 | 3 | 13 | 2.6 | 6.0s | 40 | | 7 | 7,969 | 20,457 | 680 | 0.15/s | 7.5 | 4 | 14 | 2.8 | 6.0s | 44 | | 8 | 12,750 | 33,207 | 760 | 0.15/s | 7.75 | 4 | 15 | 3 | 6.0s | 48 | | 9 | 20,401 | 53,608 | 840 | 0.16/s | 8 | 5 | 16 | 3.2 | 6.0s | 52 | | 10 | 32,641 | 86,249 | 920 | 0.16/s | 8.25 | 5 | 17 | 3.4 | 6.0s | 56 | **Grabs**1 at levels 1-2, 2 at levels 3-4, 3 at levels 5-6, 4 at levels 7-8 and 5 from level 9. Tower XP levels add to the level here, up to 6 at a time. **Distance**Each level sends enemies 0.5 tile further, from 4 tiles at level 1 to 8.5 at level 10; tower XP levels add the same again. Upgrades also raise its Power, so strong enemies travel a bigger share of that. ### Research Research (main menu, Upgrades & Research) makes every Portal you build stronger. Each item has 5 levels for 250, 750, 2,000, 6,000 and 15,000 XP (24,000 XP for all 5). #### Portal Power +10% Power a level, +50% at level 5: strong enemies are sent a bigger share of the full distance, and the landing hit grows. Weak enemies already go the full distance. #### Quick Recharge +6% recharge speed a level, +30% at level 5: the portals open more often. #### Long Reach +6% range a level, +30% at level 5. #### Height and ground - Each level of height: **+8% damage** and **+0.5 range**. - Hills: up to 15 levels on every map; above 5 is rare. - Platforms (small +1, medium +2, large +3) stack up to 3 high: up to 9 more levels, on flat ground or on a hill. Research unlocks the sizes and stacking. - Highest it can stand: 24 levels, **+192% damage, +12 range**. - On grass: **−5% damage**; no penalty on rock, or on a platform (it stands on steel, even over grass). ### Portal FAQ Can the Portal send back bosses? Yes. It has no rule against big enemies: any enemy walking the path can be grabbed. How far it goes is the Portal's Power divided by the enemy's health, armour and shield added up, at least 20% of the full distance. A boss many times stronger than the Power still goes 20%. The one thing it cannot move is an enemy under a Domeguard's bubble, and the enemies riding inside it. Can it move flying enemies? No. It grabs only ground enemies walking the path. Flying enemies, and enemies that drop or move on their own instead of walking the path, are left alone. How far does it send an enemy? 4 tiles at level 1, 0.5 tile more for every level, 8.5 at level 10; each tower XP level adds another 0.5 tile. Distance end-of-wave cards make every trip longer. That is for an enemy no stronger than its Power; a stronger one goes Power / strength of it, never less than 20%. An enemy close to the entrance only goes back to the start. How many enemies does it grab at once? 1 at levels 1-2, 2 at levels 3-4, 3 at levels 5-6, 4 at levels 7-8 and 5 from level 9. Tower XP levels count too, up to 6 at once. It takes them in the order of its target priority, skipping any it has just sent. Can it send the same enemy back over and over? No. An enemy that comes out of a portal cannot be grabbed again for 6 seconds, by any Portal. With several Portals in a row, the next one takes the next enemy instead. Does the Portal do damage? A little. Each enemy takes a hit worth 25% of the Power when it lands, which goes through shield and armour first like any hit and can finish an enemy off. It never gets Poison, Deep Wound, Armour Damage or Shield Damage cards; its damage cards are Distance cards, which send every enemy further and raise its Power. How does the Portal earn XP? From every enemy it sends: more for strong enemies, and more the further they actually go. The landing hit earns XP like any tower's damage. Its XP levels matter more than most towers': they add grabs and distance on top of its upgrades. Why did my Portal not send anything? The enemies in range were all flying, under a Domeguard's bubble, or just sent back (they are safe for 6 seconds), or it is still recharging. LOW POWER or NO POWER on it means it is short of power: it needs 20 power at level 1 and 56 at level 10. How much power does a Portal use when it has nothing to shoot? Only 1: with no target it stays on standby, lights and radar on. It uses its full power only while it has a target: 20 at level 1, 56 at level 10 (the tower panel says "uses N when firing, 1 on standby"). If the grid cannot give it that, it stays on standby too: it keeps tracking enemies but cannot fire (LOW POWER). The panel's Switch off button turns it off completely: it draws nothing and does nothing until you Switch on again, so you can choose which towers run when power is short. --- About the whole site: https://blockadebrigade.com/llms.txt