What's Changed
* [GardnerChess] Init by sotetsuk in https://github.com/sotetsuk/pgx/pull/866
* [Gardner Chess] FEN conversion by youyou-ku in https://github.com/sotetsuk/pgx/pull/867
* [Mahjong] Faster jit compile time by OkanoShinri in https://github.com/sotetsuk/pgx/pull/855
* [Hex] Add swap feature by sotetsuk in https://github.com/sotetsuk/pgx/pull/869
* [AnimalShogi] Add repetition feature by sotetsuk in https://github.com/sotetsuk/pgx/pull/868
* [GardnerChess] Add visualization by sotetsuk in https://github.com/sotetsuk/pgx/pull/870
* [AnimalShogi] Add past board history to observation by sotetsuk in https://github.com/sotetsuk/pgx/pull/872
* [GardnerChess] Add Action class by sotetsuk in https://github.com/sotetsuk/pgx/pull/871
* [Docs] Update documents by sotetsuk in https://github.com/sotetsuk/pgx/pull/854
* [GardnerChess] Add tests for Action by youyou-ku in https://github.com/sotetsuk/pgx/pull/875
* [GardnerChess] Implement step function by sotetsuk in https://github.com/sotetsuk/pgx/pull/877
* [GardnerChess] Add Zobrist hash by sotetsuk in https://github.com/sotetsuk/pgx/pull/878
* [GardnerChess] Implement observation by sotetsuk in https://github.com/sotetsuk/pgx/pull/879
* [Backgammon] Add the playable dice number to the observation by nissymori in https://github.com/sotetsuk/pgx/pull/881
* [Backgammon] use `_rng_key` by nissymori in https://github.com/sotetsuk/pgx/pull/884
* [Docs] Fix typo by sotetsuk in https://github.com/sotetsuk/pgx/pull/886
* [Seaquest] Speed up by sotetsuk in https://github.com/sotetsuk/pgx/pull/890
* [Backgammon] Train agent with ppo by nissymori in https://github.com/sotetsuk/pgx/pull/885
* [Seaquest] Speed up by sotetsuk in https://github.com/sotetsuk/pgx/pull/893
* [GardnerChess] Speed up by caching current piece positions by sotetsuk in https://github.com/sotetsuk/pgx/pull/894
* [GardnerChess] Fix past board observation by sotetsuk in https://github.com/sotetsuk/pgx/pull/895
* [Chess,GardnerChess] Fix observation by sotetsuk in https://github.com/sotetsuk/pgx/pull/896
* [BridgeBidding] Refactor `action` and `observation` to match openspiel by harukaki in https://github.com/sotetsuk/pgx/pull/889
* [AnimalShogi] Fix max termination steps by sotetsuk in https://github.com/sotetsuk/pgx/pull/899
* [Chess, GardnerChess] Fix Zobrist hash by sotetsuk in https://github.com/sotetsuk/pgx/pull/897
* [Chess] Remove castling/en passant zobrist hash by sotetsuk in https://github.com/sotetsuk/pgx/pull/901
* [Chess] Add Terminal/Observe test by youyou-ku in https://github.com/sotetsuk/pgx/pull/773
* [BridgeBidding] Add test with openspiel by harukaki in https://github.com/sotetsuk/pgx/pull/898
* [GardnerChess] Add step test by youyou-ku in https://github.com/sotetsuk/pgx/pull/882
* [Chess] Fix history length by sotetsuk in https://github.com/sotetsuk/pgx/pull/903
* [Chess, GardnerChess] Fix repetition feature definition by sotetsuk in https://github.com/sotetsuk/pgx/pull/904
* [Shogi] Fix max termination steps by sotetsuk in https://github.com/sotetsuk/pgx/pull/902
* [Chess] Take castling and en passant into account in hash by sotetsuk in https://github.com/sotetsuk/pgx/pull/905
* [Shogi] Make feature channel last by sotetsuk in https://github.com/sotetsuk/pgx/pull/906
* [API] Add `pgx.__version__` by sotetsuk in https://github.com/sotetsuk/pgx/pull/907
* Fix color features by sotetsuk in https://github.com/sotetsuk/pgx/pull/908
* Update some environments to `v0` by sotetsuk in https://github.com/sotetsuk/pgx/pull/909
**Full Changelog**: https://github.com/sotetsuk/pgx/compare/v0.7.4...v0.8.0