Put note about my fork in README.md.

README.md

@@ -1,4 +1,14 @@
 # Python MTGA
+
+## pak21 fork
+
+If you're reading this, it means you obtained this package from [pak21's fork](https://github.com/pak21/python-mtga)
+of the [original](https://github.com/mtgatracker/python-mtga). This
+fork has potentially breaking changes, please do not file any issues
+found with this fork on the original.
+
+## Introduction
+
 MTGA tools & set data for python. Original cardset generated with MTGJSON and scryfall,
 with initial set of  MTGA grpId's collected by Fugi & Spencatro.
 (Now we just use the data already present in your MTGA installation.)
@@ -22,4 +32,4 @@ Because I always forget:
 python setup.py sdist bdist_wheel
 twine check dist/*  # check for readme issues (e.g. line endings MUST BE LF, not CRLF lol)
 twine upload dist/MTGA-<version>*
-```
+```

source/allcards.py

@@ -0,0 +1,6 @@
+#!/usr/bin/env python3
+
+import mtga
+
+all_styles = [set(card.styles) for card in mtga.all_mtga_cards.cards]
+print(set().union(*all_styles))