Level Up: Advanced 5th Edition has robust encounter-building rules designed by monster-math guru Paul Hughes of the BlogofHolding, probably one of the world's foremost experts on the math behind monster stats. Those rules are equally valid for O5E (original 5E) games, so we thought we'd share them here. These guidelines can be found in the Level Up core rulebooks, available from our website.
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In the rest of the Monstrous Menagerie, Paul redesigned every monster from the Monster Manual, making them more interesting, ensuring that the Challenge Rating math was correct, and adding a ton of useful GM tools. It's a fully-illustrated 540-page book crammed full of useful information, tools, and monsters!

Level Up: Advanced 5th Edition (A5E)
Are you ready to level up your 5E game? Welcome to Level Up: Advanced 5th Edition, the standalone 'advanced 5E' backwards compatible tabletop role playing game. Level Up is a deeper, more flexible enhancement of the 5E ruleset which you know and love. If you love 5E but would like a little more...

In the rest of the Monstrous Menagerie, Paul redesigned every monster from the Monster Manual, making them more interesting, ensuring that the Challenge Rating math was correct, and adding a ton of useful GM tools. It's a fully-illustrated 540-page book crammed full of useful information, tools, and monsters!