A defensive Trigger. It's more durable the smaller it is.

Osamu Mikumo about Shield, in Osamu Mikumo 5.[1]



Ai Shield

Kanji シールド
Rōmaji Shīrudo
Organization BrDr Border
NgBr Galopoula(unnamed)
Type White trion Normal
Classification Defense Defense(Border)
- Mid to high defensive power
- Disposable
- Adjustable size (in Border)
First Appearance
Manga Chapter 8
Anime Episode 4

Shield (シールド Shīrudo?) is the primary Defense Trigger used by all known Border agents.[2] Combatants from Galopoula possess a very similar Trigger,[3] as do some types of Trion Warriors.


Shield generates an even, transparent green barrier with no default shape or size. It is most commonly seen taking a hexagonal shape[4] or a round one,[5] but it can also be molded in more complex forms, such as a crystal-like one.[6] Its shape does not need to be regular[7] and can also be convex.[8] Furthermore, it can be modified even after the barrier is summoned.[7] Galopoula soldiers generally summon pentagonal barriers.[3] The lower the surface area, the darker the color will be, mirroring the increase in density. When Shield is activated, a glowing green hexagon appears on the user's hand[9] or wrist.[8]


It is unknown when Border created this Trigger. Since some Neighbour countries use it,[3] it may be part of the technology that Border acquired in the Neighborhood. Its performance rate has been increased over time.[10]


Shield is an indispensable Trigger for all agents, regardless of their class.[11] It allows the user to generate a moderately strong barrier in a location of their choosing, including one's own trion body,[12] and its size and shape can be modified freely.[11] The smaller it is, the higher its durability.[1] It is also more resistant if kept immobile.[13] Its ability to be shapeshifted at will, even after it has been deployed,[7] makes it considerably versatile. It can protect only selected areas or the user's whole body from all directions,[6] and even be finely divided.[14] Gunners can spread it around their weapon to fire without exposing themselves,[15] exploiting its transparency.[11] Since the barrier can float on its own, either remaining fixed in place or following one's movements, the user's hands remain free.[16] Shield can also be cast around allies[17] within a radius of approximately 25 meters, although the maximum range fluctuates depending on the user's skills.[18] Multiple users can combine their Shields, juxtaposing them in order to increase the area of defense without reducing their durability too much,[8] or overlapping them for extra localized protection.[19] The act of activating Shield through both the main and the sub is known as Full Guard.[20]

Tokieda support

Tokieda saving Arashiyama.

The durability of a barrier is heavily influenced by the amount of trion the user has,[21] positively as much as negatively.[22] In general, it can withstand multiple rounds of Gunner Triggers, and in fact it has contributed to relegating Gunners and Shooters to roles of support.[10] Lightning is the sole Sniper Trigger that can be stopped with a normal Shield.[23] To block an Eaglet shot, on the other hand, it is necessary to focus the barrier to a width of a few inches, which normally requires the user to anticipate the Sniper's target and firing position.[24] However, not even a concentrated Shield can resist Ibis.[25] As for Attacker Triggers, a focused Shield can repel a stabbing attack with Scorpion without cracking,[26] but it will crack immediately if hacked at with Kogetsu and break if pressure continues to be applied.[27] A focused Shield was left undamaged from intercepting a Raygust slash accelerated with Thruster,[28] but this might have been due to the exceptionally low trion of the wielder, since the combo is normally able to cut through Escudo.[29] Shield casters with exceptional trion levels may be able to deflect Eaglet without concentrating the barrier[30] and Ibis with Full Guard.[31] Conversely, a Gunner or Shooter with vast trion reserves can break Shield with a single volley of bullets.[32]

Suwa shield

Kōtarō Suwa's focused Shield.

Shield does not interfere with Triggers which lack direct destructive power, and thus it is useless against Lead Bullet.[5] Thanks to his customized Lead Bullet,[33] Miwa can exploit this characteristic of the Defense Trigger to let his bullets go through his own Shield.[14]

Galopoula Shield

Galopoula's shield Trigger.

Warriors from Galopoula also possess a Trigger similar to Border's Shield. Their version might be more durable since, aside from blocking Viper,[34] it was able to withstand Fūjin's remote slashes with only a few cracks.[3] Like Border's Shield, the barriers create by this Trigger are transparent and can be summoned anywhere in the user's vicinity.[3] It is however unknown if their shape and size can be changed, since all the shields used by Galopoula agents were pentagonal and had roughly the same surface area.[3] Users either have at least two such Triggers in their equipment, or are able to generate two barriers with the same one.[3]


Shield is part of the Trigger set of every A and B-rank agent participating in Rank Wars,[2] as well as in Yūichi Jin's[35] and those of the members of Tamakoma First,[36] for a total of 94 known users, which makes it the most popular Trigger in Border. The total number of Shield chips, however, is a minimum of 182 as all official agents but 6 have two Shields in their Trigger set.[2] The exceptions are Kyōsuke Karasuma,[37] Osamu Mikumo[38] and the 4 Bagworm Tag users.[2] Masafumi Shinoda has also used this Trigger.[12]

Gatlin, Wen Sō and Ratarikov have also shown to utilize a Trigger very similar to Border's Shield,[3] suggesting that it may be part of the standard equipment of soldiers from Galopoula.

Humans are not the only ones who can use shield Triggers. In Border, dummies can be fitted with Shields to help Shooters practice.[39] Rodochroun, a planet-nation that specializes in the making of Trion Warriors, is able to manufacture models that can generate shields, such as Manberdo Dogs[40] and Idras. The latter are particularly remarkable for their ability to combine their shields to increase their durability,[41] but even the shield of a single Idra can withstand a Kogetsu slash without cracking.[42]


  • "Shield" is also the name of one of the seals of Yūma Kuga's Black Trigger. The two are also similar in appearance and functions, and both are more durable when fixed in place.[43]
  • Chelidon can generate circular barriers not dissimilar to Border's Shield, whose number and diameter can be increased or decreased at will.[44][45]


  1. 1.0 1.1 World Trigger Manga Chapter 36 (p. 8)
  2. 2.0 2.1 2.2 2.3 World Trigger MangaBorder Briefing File
  3. 3.0 3.1 3.2 3.3 3.4 3.5 3.6 3.7 World Trigger Manga Chapter 125 (p. 8)
  4. World Trigger Manga Chapter 26 (p. 3)
  5. 5.0 5.1 World Trigger Manga Chapter 29 (p. 6)
  6. 6.0 6.1 World Trigger Manga Chapter 8 (p. 16)
  7. 7.0 7.1 7.2 World Trigger Manga Chapter 112 (p. 10)
  8. 8.0 8.1 8.2 World Trigger Manga Chapter 100 (p. 7)
  9. World Trigger Manga Chapter 29 (p. 7)
  10. 10.0 10.1 World Trigger Manga Chapter 107 (p. 8)
  11. 11.0 11.1 11.2 World Trigger MangaBorder Briefing File (p. 220)
  12. 12.0 12.1 World Trigger Manga Chapter 71 (p. 13)
  13. World Trigger MangaBorder Briefing File (p. 303)
  14. 14.0 14.1 World Trigger Manga Chapter 76 (p. 4)
  15. World Trigger Manga Chapter 112 (p. 1)
  16. World Trigger Manga Chapter 99 (p. 7)
  17. World Trigger Manga Chapter 29 (p. 5-6)
  18. World Trigger Manga Chapter 74 (p. 20)
  19. World Trigger Manga Chapter 60 (p. 17)
  20. World Trigger Manga Chapter 26 (p. 16-17)
  21. World Trigger Manga Chapter 113 (p. 11)
  22. World Trigger Manga Chapter 29 (p. 15)
  23. World Trigger Manga Chapter 33 (p. 19)
  24. World Trigger Manga Chapter 89 (p. 7)
  25. World Trigger Manga Chapter 113 (p. 14-15)
  26. World Trigger Manga Chapter 143 (p. 16)
  27. World Trigger Manga Chapter 99 (p. 6)
  28. World Trigger Manga Chapter 143 (p. 11-12)
  29. World Trigger Manga Chapter 172 (p. 4)
  30. World Trigger Manga Chapter 111 (p. 11-12)
  31. World Trigger Manga Chapter 114 (p. 14)
  32. World Trigger Manga Chapter 113 (p. 18)
  33. World Trigger MangaBorder Briefing File (p. 79)
  34. World Trigger Manga Chapter 125 (p. 16)
  35. World Trigger MangaBorder Briefing File (p. 99)
  36. World Trigger MangaBorder Briefing File (p. 91-95)
  37. World Trigger MangaBorder Briefing File (p. 95)
  38. World Trigger Manga Chapter 164 (p. 15)
  39. World Trigger Manga Chapter 109 (p. 15)
  40. World Trigger Manga Chapter 130 (p. 4)
  41. World Trigger Manga Chapter 124 (p. 10)
  42. World Trigger Manga Chapter 129 (p. 10)
  43. World Trigger Manga Chapter 15 (p. 19)
  44. World Trigger Manga Chapter 54 (p. 16)
  45. World Trigger Manga Chapter 59 (p. 12)


e - d - vBorder Triggers
Basic Equipment Bail OutRadarTrion Body
Attacker Kogetsu (Kogetsu: Spear) • Raygust (Shield Mode) • ScorpionSōgetsu (Axe)
Gunner Asteroid • Cobra • Gimlet • Hornet • HoundMeteorSalamanderTomahawkViper
Firearms Assault Rifle • Grenade Launcher • Handgun • Minigun • Shotgun
Sniper EagletIbisLightning
Defense EscudoShield (Affixed Mode/Full Guard)
Trap Switchbox
Optional Bagworm • Bagworm Tag • ChameleonConnector • Dummy Beacon • Enhanced Radar • Full ArmsGeistGen'yōGrasshopperIdatenLead Bullet • Makō • Senkū • Silencer • SpiderStarmakerTeleporterThruster • Timer
Prototypes Connector • Dummy Beacon • Full ArmsGeistIdaten • Makō • Teleporter • Timer
Black Fūjin • Tsukihiko Amō's Black Trigger • Yūma Kuga's Black Trigger
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