The Memento is a special building released with the 1.30 Update. The only way to get a Memento was, when a player which you have invited reaches Iron Age[1]. It is classed as a decoration and provides happiness and can be polished.

Happiness

Age Happiness
BA +90
IA +100
EMA +110
HMA +120
LMA +130
CA +150
INA +170
PE +190
ME +200
PME +210
CE +250
TE +300
FE +360
AF +420
OF +480
VF +580
SAM +920
SAAB +1,000
  1. This building is not part of the invite rewards anymore - those solely consist of Diamonds diamonds nowadays

Other Special Buildings

Special Buildings
Residential Buildings Abandoned AsylumAirshipAltar GardenAncient ObeliskAthlete Living QuartersBlack TowerCaravansaryCharming CottageCheckmate SquareClassical Garden PatioColossusContestants' EstateDark DoorwayEastern Palace TowerElephant Fountain GateEmperor's EntranceFaery RingsFishing HutForest of FallGingerbread HouseGovernor's VillaGrand BridgeGreater RunestoneHanami BridgeHarvest BarnHaunted HouseHippodrome CarceresHippodrome SphendoneHouse of HorrorsJade StatueKing StatueKioskLog CabinMaharaja's PalaceMemorial ChhatriMenagerieMill of FallMoon GateMoose MeadowOasisObelisk GardenOlympic TreasuryPagodaPillar of HeroesPiazza CafePiazza HomesPole HouseQueen StatueRenaissance MansionRenaissance VillaRoyal BathhouseRoyal CascadeRoyal Marble GatewaySacred Sky WatchSeptember CottageShinto TempleShrine of AweShrine of InspirationShrine of KnowledgeSnow GlobeSpeaker's CornerStatue of HonorStranded BoatStraw HutSugar Baker's BoothSunflower PatchSun TempleSundial SpireThe Crow's NestThe KingThe Lord's ManorThe QueenThe ShipTholos of IdolsTimeless DojoToymaker's BoothTribal SquareWestern Palace TowerWinter BakeryWinter SpireWinter TrainWorld's FairYggdrasilZen ZoneZiggurat
Production Buildings Arena of VictorsAviaryBazaarBeach BarCider Mill / Blooming / Fruitful / Bountiful / Prosperous / FlourishingConfectionary / Large / Huge / LegendaryFan ShopFoeberge ShopGondola Dock MarketLuauMad Scientist's LabMagnum OpusMasquerade BallReindeer PaddockRosariumSanta's WorkshopSleigh BuilderSoccer FieldSunken TreasureTerrace FarmWitch Doctor
Cultural Buildings Balloon SiteBotanical RotundaCarouselClassical Garden PoolDruid WillowElephant FountainGlobe FountainGrandstandGraveyard / Old / Ancient / Legendary / Monumental / NecropolisHaunted TowerMaypole / Mighty / MajesticOrnate BathsPavilionPiazza Clock TowerPond of FallPrimrose BloomSandcastleTigers' DenWinners' PlazaWinter GateWinter MarketWinter Pyramid
Decorations Award TrophyBandar PlaygroundBleachersBronze AwardCandlemaker's TentChhatri GardenClassical Garden StatuesDecorated BaobabDining CarFace of the AncientFestive TreeFoE CupForge Bowl TrophyFreight CarGarden RuinsGate of the Sun GodGate Statue EastGate Statue WestGift TowerGold AwardHalmbockHammockJack O'Lantern ChapelLeukoi TrackMaharaja's Jungle PondMask StatueMementoMobilithNeighborhood CupNishikigoi PondNutcrackerOchre YardPalm TreePhoenix StatuePiazza FountainPirate Guard PostReindeer SleighRoad to VictoryRousioi TrackRoyal Guard PostSakura RockScarecrowSilver AwardSleeping CarSmörgåsbord FeastSphinxStanding StoneStone AwardSundialTiki TotemTinkerer's TentTitan Arum PlantTrader Guard PostTree of Love / Great / EternalVenetoi TrackVenice CanalVitruvian ManWell of WelcomeWheat FieldWisteria TopiaryZanni Mask Statue
Military Buildings Champion's RetreatColor Guard CampDrummer SchoolRogue DenRogue Hideout
Other Buildings Antiques DealerArctic HarborAutumn ScarecrowBegonia BenchFountain of YouthFriends TavernGong of Wisdom Level 1 / Gong of WisdomHall of FameHedge MazeMadame Fortuna's TentMajestic Fawn/StagMonasteryOceanic TerminalPiazza Mask VendorRitual FlameSentinel OutpostStraw Star TentTactician's TowerTown HallVictory TowerWatchfireWishing Well / Little
Building Items FragmentsOne Up KitRenovation KitSelection KitShrink KitStore BuildingUpgrade Kit
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