EN Publishing is rightly regarded as producing high-quality products. Arcane Strife is no exception. But let's get a few things out of the way first. Yes, the last thing d20 (of any edition) needs is more flexibility and power for spellcasters. Yes, the last thing a player of a d20 spellcaster needs is a list of 200 more spells to try to choose from.
But if you already feel your campaign is teetering under this weight, why are you even paging through d20 supplements online? In this review I'm going to assume you already want a d20 fantasy supplement for spellcasting and magic, for whatever reason: you're designing a campaign and want a unique feel to magic, your'e tired of games with everyone knowing the same old spells and want to toss some old ones and put in some new ones, you handle game balance in other ways, you and your players love digging through mounds of options and debating them in and out of character. So you're here because you want to buy a d20 magic supplement and you're trying to decide if Arcane Strife is it.
First, there's a printer-friendly version whose primary change is to remove the color background. Although the version with the color background is marked "screen version", really there's nothing about it that makes it suitable for a screen in particular, such as landscape orientation or variable flow. It's really just a more colorful PDF. The cover is also in the ZIP file in case you want to make yourself a nice-looking copy. The table of contents is very well done, including subheadings for the spells by initial letter. If I had to criticize anything about the organization of the work it would be that some of the spells are not well-described by their initial letter, so having a more extensive index or hyperlinks within the document itself would be an excellent idea.
The work starts with a bombshell of a system that describes how magic works on the world of Shtar, the world described inside Arcane Strife - basically when a spellcaster is interrupted (via the normal Concentration rules), they may permanently lose the spell slot and be badly damaged. It's interesting, but I think spellcasters who are going to be doing casting where they might have to make a Concentration check are going to have a Concentration skill level sufficiently high that it's not going to do much. I think it might be better to just require the damage in the form of subdual (magic is tiring to cast) or make it based on some kind of physical prowess that spellcasters are unlikely to have (a Fortitude save or something). Anyway, it's a really interesting start, not what you normally expect from a book of this kind.
There's a few other little magic systems that are introduced, wizard's sigils and true names and so on, then a thankfully brief list of feats. The bulk of the work is taken up with an extensive spell list. Interestingly, the spell descriptions begin with a vivid fictional description of its origin, such as the wizard who invented it, or the war it turned the tide of. I would like to see more games use these, especially for campaign creation, as they help me fit the spells into the tapestry of the world.
The prestige classes are very interesting, though they need even more attention in fitting them into a campaign. I'm not sure how a Master of Minor Magic would be played as a PC, an ally or a villain, for example, as interesting as the idea (a Master of Minor Magic consistently increases the power and number of spell slots for lower level spells instead of higher level spells) might be.
Finally, there are several creature templates, most related to some of the magical effects in the book. Like the prestige classes, these templates might have benefitted from some explanations as to personality, roleplaying, or encounter opportunities.
All in all, Arcane Strife is very well presented and has many cool ideas. it's hard to go wrong with EN Publishing. However, I think the best ideas in this work are the ones that are fully developed and integrated into the world described. The prestige classes and creature templates are just left out there for me to decide how they fit in, or what effect they might have on my game world if I eagerly throw them in willy-nilly.
A solid outing, good work all around.