?Overcasting: D20 Magic Variant? is a very focused four page product which sets out a system governing casting spells after a spell casting character has used up all available spell slots. Half of the first page is devoted to the cover image and the final page is devoted to the Open Game License, which leaves just over two pages of game content. The first half of the text on the first page sets out a short story about a spell caster that expends his last spell only to find that some enemies have survived.
The system presented in this product relies on the caster making the attempt having the Overcasting feat. In addition to requiring the feat, overcasting results in the caster losing experience points. The product then sets out the specific effects of overcasting on bards, clerics, druids, paladins, rangers, sorcerers, and wizards. These take effect after the resolution of the spell. The product presents six possible effects of overcasting and requires the player to roll 1d6 to determine which occurs. These effects range from saving throw penalties, temporary ability score damage, damage to a animal companion or familiar, loss of a spell slot, and permanent ability score damage. The mechanics presented provide the player with an opportunity to apply a modifier to the effects roll which reduces the severity of the effects or, if lucky on the roll, to eliminate the negative effect entirely.
The innovative dungeon master is likely, after reviewing the lists, to add additional effects. In fact, the product closes by suggesting six different rule variations, with each one making overcasting more and more costly or dangerous. The combination of the 1d6 roll to determine the negative effect of the overcasting and the possibility to apply a modifier to the roll make for a simple yet fairly random mechanic.
Overall, this is an interesting product which presents a simple yet elegant mechanism for something that every spell caster has wanted to do at some point. If you would like to include overcasting rules in your campaign but do not want to develop your own mechanics, this product presents a viable starting point.
To rousing gaming and ample rewards,
1. Short and focused.
2. Development of a popular concept.
1. Inclusion of superfluous short story as introduction for such a short product.