Tell me more about 13th Age and dungeons. I had bounced off it early on for whatever reason and never looked into it again.
Must control fanboy inclinations.
You see, I love 5e. But 13th Age is my favorite D&D-like RPG. It's a d20 that came out less than a year before 5e, done by one of the lead designers of D&D 3.0 (Jonathan Tweet) and the lead designer of 4e (Rob Heinsoo) as "the game we want to play in our Wednesday night game". The describe it as "a love letter to D&D", and despite the pedigree it shares a lot of the same streamlining 5e does.
It revamps some of the underlying mechanisms about other pillars of play. First the skill system is replaced by backgrounds. Backgrounds are freeform and designed to be descriptive and broad. So you not "Sailor +4", you're "First mate on the Pirate Galley Roll-yer-Bones". Will that come in while sailing? Sure. But also dealing with dockworkers, finding some shady smuggling connections, and in drinking contests. There's an example I think Rob Heinsoo gave about a convention game where someone had been a military officer on the Sea Wall (attacked regularly by giant kaiju). They were trying to console a woman who they just told their son had died in a military action else. When asked for a roll, the officer was "do you know how many letters I've had to write to the families of our young soldiers?" Boom - background appropriate, use it.
PCs all also have One Unique Thing. It's something, well, unique about them that doesn't provide straight abilities or pluses. It could be a mechanical heart made by the dwarves, or beign the only halfling knight in the kingdom, or being the Emperor's 13th bastard child, or the only acrobat to ever escape from the Diabolist's Circus of Hell. Did the Circus of Hell exist 30 seconds ago? Nope. But now it's canon.
Another point is that PCs have connections - good, bad, or "it's complicated" to the various movers and shakers of the realm. These are called the Icons, and they are big figures, some full of shades of great and some seeming more stark. The last campaign I ran of it the Elf Queen ended up to be one of the biggest bads of the campaign, manipulating other Icons in a subtle, decade long bid to wipe humanity off the map.
Getting back to revamping pillars of play, wizards can cast any spell as a ritual, and basically free-form reshape it with the DM to fit whatever non-combat need wanted. Want to dazzle a settlement with an amazing fireworks display that will shock and awe them? Sounds like 1d4 minutes casting fireball. Need to superheat the forge so it can smelt the ultra-rare metal and make your magic item? What, you want to use fireball for that? Okay, but it will take 1d4 hours.
Because spells can be turned to whatever non-combat uses you can imagine, they only really need to detail them otherwise for combat, a place where we want hard numbers. Casters have a limited number of slots, but they go up in level and every single spell can be upcast. So a mid level caster might have 3rd-5th level slots and no more 1st level.
Spells are also either at-will, per-encounter, or per-day, with some variations available. Your high level caster going into a war and needs to be able to be a devistating caster all day? Take the at-will Magic Missile in a 9th level slot. Boom. Literally.
Between OUTs (One Unique Thing), Backgrounds, Rituals, you should be getting the impression that the system welcomes putting some narrative control in player hands. This is true.
It also supports DM hacking - there's copious sidebars with direct info from the designers - why they did a certain rule that way, the effects of tweaking other rules. Heck, where they disagreed and what each of them proposed as well as why they went with what they did. The curtain is definitely pulled back and makes it a system you can tinker with easily.
Oh gosh, I could go on for pages about the changes and why I like it. Incremental advances (not waiting for a level to get goodies), the Escalation Die (makes combats more tactical in when you o things as well as less grind-y), and a bunch of others.
But before I end, I do need to go one one last bit. The monsters in the core book are very D&D reminiscent. But they didn't hold themselves to that limitation for the two Bestiaries. They are perhaps the very best monster books for any RPG I have ever read. Full of hooks, encounter building, practical advice - these books know that they are to be used to make adventures and live up to that promise. They drip with flavor and awesome, have hooks and connections galore, and give practical advice about running them.
Oh, and one non-system thing - the publisher Peregrine Press runs Bits and Mortar. Basically, regardless if you buy a hardcover from them or from your FLGS, they will give you the PDF for free.