AKARANGER: in 199 hero great battle, akaranger appears and gives the gokaiger the goranger grand power; the varibloom. he will also apear in the final episode.
BIG ONE: in 199 hero great battle, souchiki banba returns and gives the gokaiger the grand power of JAKQ which has yet to be revealed onscreen
note: big one is portrayed by the same actor who played ioranger in goranger, as well as the title characters of kamen rider V3 and zuubat
BATTLE FEVER J:
BATTLE KENYA: battle kenya first appeared in gokaiger episode 44 as a mall santa and gave the gokaiger the battle fever grand power as a christmas present. battle kenya later appeared in GOKAIGER VS GAVAN, he transforms in the movie and fights with gavan and denji blue.
DENJIBLUE: denji blue returns in 199 hero great battle and gives the denjiman grand power to the gokaiger. he also appeared in gokaiger VS gavan, and transformed along with gavan and battle kenya.
the second vul eagle appears in episode 48 alongside green flash, blue mask, change griffin, and five yellow, the sun vulcans main hangout has appeared in gokaiger episode 1
GOGGLE BLACK: in 199 hero great battle, goggle black returns and gives the gokaiger the grand power of goggle V
DYNAPINK: in 199 hero great battle, dynapink returns and gives the dynaman grand power to the gokaiger
RED 1: in 199 hero great battle, red 1 returns and gives the grand power of the bioman to the gokaiger
CHANGE GRIFFEN: change griffen appears in episode 48 alongside vul eagle II, five yellow, blue mask, and green flash.
GREEN FLASH: green flash appears in episode 48 alongside vul eagle II, five yellow, change griffen, and blue mask.
BLUE MASK: blue mask returns in episode 48 alongside vul eagle II, five yellow, green flash, and change griffen.
YELLOW LION: jou appears in episode 30 and gives the gokaiger the grand power of the liveman, as well as giving joe barizorgs orignal blueprint.
BLACK CONDOR: in gokaiger episode 28, when we first see him, he is in his persanal heavan(a bar) playing a game with a goddess, which he wins, the goddess lets him return to earth for one day(because he doesnt like heavans wine) and can only be seen by the gokaiger(save for gai, most likely since he is human). while back on earth, gai yuuki once again becomes black condor. the episode ends with gai back in heavan playing the saxaphone for the goddess.
DRAGONRANGER; in episode 18, dragon ranger appears alongside abarekiller and timefire and gives gai the power of the gou jyu rex.
RYUURANGER: ryo returns and gives the grand power of dairanger to the gokaiger. in episode 33, ryo apears again and gives the gokaiger the dairanger grand power in person.
NINJAMAN: ninjaman returns in episode 45, revealing that he was trapped in a vase and wasnt able to fight in the hero great war, and have his power converted into a ranger key. he is able to become a mech sized warrior called "samuraiman". when he was found by the gokaiger, he had them change into blue rangers and lion themed rangers, as well as dressing in old-age japanese clothing and make him food for the kakuranger grand power.
NINJAWHITE: ninjawhite also appears in episode 45, as a cameo near the end.
OHRED: in episode 31, ohred appears as the current general of U.A.O.H and has a speaking cameo in episode 32
OHPINK: in episode 31, ohpink appears at an amusement park and tells the gokaiger that she has the grand power of ohranger. in episode 32, she makes a brief cameo and the ohranger grand power is used for the gokai galleon buster
RED RACER: in episode 14, red racer appears and gives the gokaiger kurai magic, the said grand power of carranger. since episode 14 was a carranger tribute, when red racer did a legend shift, he noticed the shadow and slapped it.
MEGA RED: kenta/megared appeared in episode 39, giving the gokaiger the megaranger grand power as well as disguising them as students in the university he went to during megaranger and now is head of.
GINGARED: gingared returns in episode 20 where he is shown to still living in the forest from gingaman.
BULL BLACK: bull black appears in episode 20. he is the first nonred senshi to receive a legend shift. his key holds the gingaman grand power.
GOPINK: gopink returns in episode 23 and gives the gogoV grand power to the gokaiger after trusting ahim and luka(the main focus on the episode)
TIMEFIRE: in episode 18, naoto returns and gives gai the gou jyu drill
TIMEYELLOW: domon appeared in the main timeranger tribute episode(which explaines how the gokaiger appeared in GO-ONGER VS SHINKENGER). by the end of the episode, domon finds a picture of the gokaiger with a women and little boy. he realized there that the women was the girl he had a crush on during the course of the series, and that was there son, and his past desendant that he never met. this was brought up in the series, just domon never knew his girlfriend was pregnent.
GAORED: in episode 9, kakeru returns and gives the gokaiger gaolion, the gaoranger grand power. since the end of gaoranger, kakeru has become a vet.
all three of the main hurricanger(yousuke, nanami, and kouta) return in episode 25 and 26. in episode 26, the hurricanger and gokaiger team up(gai had given the hurricangers there ranger keys back) the hurricanger give the gokaiger the hurricanger grand power; furai maru.
note: it was never explained why nanami is with the hurricangers again since when we last saw her, she was a famous actress
ABAREKILLER: DR mikoto gives gai the goujyu jin in episode 18 with timefire and dragon ranger
ABAREBLUE: yukito returns in episode 29 and gives the gokaiger the rest of the abaranger grand power. since the end of abaranger, he has married emiri, who was ally to the abaranger.
ABAREPINK(UNOFFICIAL): emiri was not an abaranger, but in one episode she became an unofficial senshi, abarepink. in episode 29, she appears and gives ahim the "abarepink key", ahim uses it despite not knowing that the suit was so makeshift. while in abaranger, emiri dressed like a steryotypical nerd, here she looks more basic, implying that after that she and yukito got married, he gave her a drastic mekeover so they could be seen in public togethor
DEKAYELLOW: in episode 5, jasmine appears and cuffs marvelous since he was a pirate with a high bounty on his head.
DEKAMASTER: anubian doggy krueger appears in episode 5 and gives the gokaiger the grand power of the dekaranger. he also briefly appears in gokaiger goseiger 199.
DEKARED: ban cameos near the end of the episode after krueger is injured and the gokaiger defeat the action commander.
DEKAPINK: umeko appears in 199 hero great battle and gives the gokaiger some extra dekaranger power(probably to supplement the extra dekaranger) she most likely appeared since in real life she is married to red racer, who had previously appeared.
MAGIRED: a matured kai appears in episode three, now sporting a red streak in his hair similiar to the human momotaraus from KAMEN RIDER DEN-O. he gives the gokaiger the grand power of magiranger after gaining trust in marvelous and don.
BOUKEN RED: akashi retrurns in 199 hero great battle and give the gokaiger the grand power of the boukenger, and in episode 21, he reappears to give it to them in person. he knew akared, a partner of marvelous.
GEKIRED: in episode 7, jan returns and teaches don and ahim the ways of geki jyuken, as well as give the gokaigers the gekiraner grand power.
MASTER SHA-FU: an ally to the gekiranger, sha-fu cameos at the end of episode 7 where he is seen talking to jan.
GO-ON RED: in episode 35 and 36, sosuke returns and gives the gokaiger the go-onger grand power. he is seen in gunman world(the last brane world to be seen) with the engines and BOMPER
ENGINE 1 speedor: sosukes engine partner and the father of engine 13 machalon
ENGINE 2 buson: go-on blues engine partner.
ENGINE 3 bearRV: go-on yellows engine partner and the mother of enginge 13 machalon
BOMPER: the robot ally of the go-onger built by engine 9 jum-bowhale
GO-ON YELLOW: she appears in 199 hero great battle and gives the gokaiger the grand power of go-onger which they directly received by sosuke. she later appeared in THE FLYING GHOST SHIP as part of G3 prinsessse.
GO-ON SILVER: she appears in THE FLYING GHOST SHIP as part of the G3 prinsesses.
FEMALE SHINKEN RED: kauru shiba appears in episode 11 and 12 and gives the gokiager the shinkenger grand power(which supplements gaolion since gaored and shinkenred both use lion mechs) as well as a hidden disk for joe.
TOSHIZO TANBA: kauru's sensei and assistant.
SHINKEN GREEN: chiaki tani appears in 199 hero great battle and gives the gokaiger more shinkenger power
SHINKEN GOLD: genta unemori also appears with chiaki.
the five goseiger return and transform along with the gokaiger and gives them the goseiger grand power.
GOSEI KNIGHT: the sixth goseiger who is not a gosei angel who also appears with the others. when the goseiger first appear, they demand the gosei knight key(which the gokaigers had just gotten from basco) but the gokaigers do not recognize it.
V35/AKARED: the soul of all red senshi and finder of all the ranger keys as part of the red pirates.
GAVAN: the orignal metal hero that teams up with the gokaiger in GOKAIGER VS GAVAN, and fights with denji blue and battle kenya.