8ch
formerly 8chan, AKA infinitechan, cripplechan, fullchan, doublechan
simple global rule: no content illegal in USA
Anons can create their own boards with their own rules, settings, looks and mods.
2nd biggest English IB, still not dead
https://8ch.net
http://fullchan4jtta4sx.onion/ #Tor mirror, can't post images though.

nntp-overchan
AKA NNTPchan, overchan
network of independent image boards synced together
Every node can decide its own moderation, boards, looks, etc..
Its decentralized/federalized nature makes it very resilient against attacks and admin fuckups.
Usually hosted on Tor or I2P to ensure full anonymity both node and user. Also less hosting problems.
While it's possible to have illegal content most nodes are clean and don't allow CP.
links to few nodes:
oniichan:
http://oniichanylo2tsi4.onion/
http://g7c54d4b7yva4ktpbaabqeu2yx6axalh4gevb44afpbwm23xuuya.b32.i2p/
lolz:
http://lyp6sf5tzd6mbnmc.onion/
http://wqjsmjiwdcpx7dtm6rszd5viirirabf6lazv54uhhtti4iu5ryca.b32.i2p/
https://nntp-chan.net/overview.html
fargoth:
http://lp4t52xp5vlhyhkb.onion/
404chan, focused on Russian:
http://ofxof5euur2kg7gxqcajvu4n6hje6lrqizu6rzpvif7pceyjn67a.b32.i2p/