Download Microlite5E here and let me know what you think.
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Microlite20 was written by Robin V Stacey in 2006 with the goal of being:
… a trimmed-down, subminiature version of [Dungeons & Dragons third edition] that has been designed to be quick and easy to play. The goal was to create a simpler game, but one where all of the resources of [D&D] (monsters, spells, adventures and equipment) could be used without conversion.
Microlite5E is my attempt to do the same for Dungeons & Dragons fifth edition. It should make character creation very quick and reduce the number of fiddly bits that a player has to keep track of. Characters should be balanced with existing fifth edition characters and be able to complete normal fifth edition adventures.
Changes: Microlite5E keeps all class features, but simplifies weapon and armour choices, replaces skills with broader proficiencies, reduces races to a single feature, prompts an optimal ability modifier array and discards ability scores to use modifiers only.
It also comes with a two-page monster creation system that should make DMG-legal monsters.
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An example character:
Sage Tiefling Monk.
STR +1, DEX +4, CON +2, INT +0, WIS +3, CHA -1.
HP 10, HD 1d8, AC 17, Saves proficient STR and DEX (+2), advantage on Tiefling
Two unarmed +6 (1d12+4), dart +6 (1d6+4)
Skills Tiefling, Monk, Sage
SQ unarmoured defence, martial artist; hellish rebuke 1/day, resist fire; Researcher
Equipment shortsword, 10 darts, dungeoneer’s pack, a bottle of black ink, a quill, a small knife, a letter from a dead colleague posing a question you have not yet been able to answer, a set of common clothes, belt pouch (10gp)
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And a character sheet: http://fossilbank.wdfiles.com/local–files/source%3Achris-sakkas/microlite5e%20character%20sheet.png
Grim Portents 
Hey, I’m working on my own Microlite20 5e, and I was wondering if you could give me permission to adapt you monster-building rules. I know you’ve licensed this under Creative Commons, but I’ve already licensed my work under the OGL. In order to avoid a legal headache, I was wondering if we could reach some sort of arrangement? (If not, would you have advice on how to have the two licenses happily co-exist in one work?)
Hey Roberto, that’s great – would you mind sending me a copy of your Microlite20 5E? I’d love to take a look at it (sanglorian@gmail.com).
My strong personal preference is for Creative Commons Attribution-ShareAlike instead of or as well as the OGL (you can apply any number of copyright licences to your own work), but I’ve no real objections to you using any part of Microlite5E under the OGL.
Declaration of Open Game Content: The entirety of Microlite5E that is copyright Chris Sakkas is released as Open Game Content under the Open Game License v1.0.
SECTION 15
Microlite5E, 2015 Chris Sakkas: https://grimportents.wordpress.com/2015/01/07/microlite5e-a-trim-hack-of-5e-thats-backwards-compatible/
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Microlite5E, 2015 Chris Sakkas: https://grimportents.wordpress.com/2015/01/07/microlite5e-a-trim-hack-of-5e-thats-backwards-compatible/
Actually, scrap the part about you applying two licences to your work. I dug up a copy of M20 Fifth (http://blog.retroroleplaying.com/2015/05/fourteen-new-free-microlite20-downloads.html) and I see you’re drawing heavily on previous OGL-licensed works (which is great! But the Creative Commons Attribution-ShareAlike licence can’t be applied to most of it).
Thank you for allowing me to use your Microlite5e under the OGL! I appreciate your time in this matter.