Category:Morphology
Feature:Case Syncretism WALS
Name:Core cases only
Languages (79):
Conlangs (69):
Kamakawi
Lembrin
Old Adpihi
Saya
Quenya
Chamanar
Modern Arithide
Ryupisasa
Dainyu
Mavakhalan
Kuyʔūn
Alopian
Annese
Ruzian
Eezee
Rossan
Sjal
Dacayan
Shuran
Larler
Emyt
Kassunetian
Celdirin
Rarlang
Tlaymyts
Qitatyattas

Intransitive case and absolutive-accusative case are identical in non-singular numbers, they are only differentiated in singular forms of some nouns.
L'starfish Klam
Enterdese
Modern low Ponuhi
Maksinaunminverbe
Femmish
Apelcheq Maulochsab
Khulls
Riagi
Lohsee
Mezhat 
Case syncretism can be predicted by noun class -- pronouns and human nouns are marked in a nominative-accusative manner, while lower animates follow an ergative-absolutive pattern.
Proto-Toroq
Vtayn
Literary Fire
Deinau
Alfen
Opus
Hux Kham
Trayks
Interlingua Antic
Ganur Lon
Khan Nilau Khaftim
Pannonian
Kachan
Pejlanrau Khanech Khaftim
Saftian
INS
Gan Dostau
Kayronic
Vayardyio
Nylaf
Kavrinian 
in inanimate nouns, the nominative case and the accusative case are always the same; in animate nouns, however, the nominative case and the accusative case are always different.
Least Average
Nicho
Fsonkers
Sylvan
the I-Picked-Some-Random-Features-With-a-Die Language)
Jafian 
Jafian genetive, partitive, accusative and illative have identical forms in all nouns and adjectives. In pronouns this is true only for partitive, accusative and illative. Adessive and allative have identical forms in all nominals.
Keltsvian
Toníntaíjo Tóxe
Gwaxol
Oltic
Standard Sievi
Tenshorian

Natlangs (10):
English
Basque
Fijian
Greenlandic (West)
Mangarrayi
Oromo (Harar)
Paumari
Warao
Yaqui
Yukaghir (Kolyma)