Advanced Artificer Tips & Tactics

I think armorer is the best power builld subclass. 

Cartographer is probably the best support subclass.

All artificers start off a bit weak though. 

Magic item replication can give you a bag of holding and other neat items in early levels. (You will probably dump strength and an armorer subclass plate armor weighs a LOT, so you will always be close to being encumbered, meaning you will need that bag of holding). But an armoer's access to more rare items tapers off by level 10 or so. If you are playing in a high-magic world, by level 10 you can probably buy better magic items than you can replicate.

The spellcasting item at level 11 is probably the big power jump. You can put a level 3 artificer spell in the item after each long rest and cast that spell 10 times.

Keep in mind artificers are half casters and dont get firrball by default. So if you want to use spellcasting item to cast fireball 10 timrs a day, you have to choose artillerist subclass since thats the only subclass that gets access to fireball.

You will also run out of attunement slots quickly. The best replicate item plans require attunemnt, but by level 8 or 10, you can buy better items than you can replicate, so you will end up replicating non attunement items, like helm of awareness that gives you advantage on initiative.

Things to look for are magic items that dont require attunement and tend to be single use and then dispose. Like the Elemental Gem will allow you to summon an earth elemental for one hour, and then the gem loses its power. As an artificer, you can build that gem every morning after a long rest, giving you a earth elemental a day.

Most features rely on intmod, so max your int to 17 at level 1 and take half feats that increase int whenever you can.