RPGWatch reviews Space Siege and is not overly impressed by the sci-fi action RPG, giving it a 2/5.
The action-RPG genre has evolved around a few key elements: waves of enemies to kill, level-up schemes that feed skill trees to give you new ways to kill waves of enemies, and picking up cool loot that will allow you to more efficiently kill waves of enemies and gold to buy more loot. It is not the deepest of role-playing foundations to begin with, but it is largely satisfying when done well as in games like Titan Quest or Nox or even Dungeon Siege II. But imagine what would happen if you simplified those core elements even further? Would there even be anything left to allow a role-player to sink their teeth into?
Look at the core elements of Space Siege: waves of enemies to kill, skill points doled out at fixed intervals, and 'upgrade parts'. Let's look at the last two in more detail.
There are no 'levels' as such in Space Siege, so you don't get to mess around with attributes and skills on a regular interval as you hit a new level. You only get a skill tree and skill points that are given out after completing tasks key to the story. For example, you need to find a part for the doctor, and when you do so you get 2 skill points. You can then go to the skill tree and choose how to assign your points. There are combat and engineering skills to choose from, many of which have requirements before you can take them on. You might need certain levels in another skill or a minimum total engineering skill count, or you might need certain cybernetic implant or percent humanity. The skills are mostly passive things like increased offense or defense, and are immediately useful. Because there are relatively few skill points given you have to pick and choose your skills carefully. If you choose to use cybernetics you will have to be even more careful. There aren't nearly enough skill points to master all things. That almost sounds like choosing a class...but it isn't. These are just skills to help you cruise around and kill stuff - or at least survive the waves of attacking Kerak.
When you kill enemies or open crates or blow stuff up, you will often see 'loot' left around. So cool! This is the stuff an action-RPG fan dreams of...or not. What you gather up (pressing a key to pull it all in, which is one of those nice additions that have evolved through the years) falls into three categories: 'weapon packs', 'med packs' or 'upgrade parts'. Weapon packs are basically grenades, and med packs appear often enough to help you attempt fill out your meager inventory limit of four. These are useful and relatively obvious. But the last one is perhaps the most controversial element of the game. It comes down to this: you find no weapons, no rare weapons, no unique and powerful weapons or armor sets, nor do you find any bags of gold - you find upgrade parts.