I have been replaying Super Robot Wars: Original Generation 2 quite a lot over the last week or so (I have completed 23 out of 43 missions so far), and replaying that game has given me a lot to think about regarding good and bad ways a game can present victory conditions and optional objectives to a player.
Missions in Super Robot Wars: OG2 can be very complex and involved, which I think is a very good thing. For example, one mission is split into two phases: the first requires you to lure a number of enemy units outside of a certain area and then destroy them within a time limit, and in the second phase both you and the enemy are reinforced with additional units and you must reduce the enemy commander's hit points to less than 70% of maximum. Mixed in with these two phases are a number of different story events, hidden requirements for unlocking secret units, many opponents you can fight in order to gain experience and money, and an optional "Battle Mastery" mission objective. This kind of complexity is typical for a mission in that game, and I think that such complexity is great. However, there are a number of things I need to criticize regarding this structure.
First off, I need to mention the way the victory conditions themselves are stated. In the above example, the victory condition in the first phase is stated explicitly, but the victory condition in the second phase is stated as "Defeat All Enemies," even though the only factor that determines actual victory is in fact the hit point total of a single foe. The victory condition "Defeat All Enemies" is in fact extremely unreliable in that game, and is listed in the victory condition menu when the actual victory condition can mean anything from "Defeat 15 enemies, at which point the enemy reinforces and conditions change" to "Either bring the boss's life down to 50% or wait three turns." Also, if there happens to be multiple victory conditions, or a victory condition happens to be optional, it is never specified, and only a single victory condition is listed as if it were the only one. This vagueness can often frustrate me to no end, especially when I misdirect time and energy towards one goal, only to result in me not having enough time and energy to accomplish the real mission objective. I think that games should be honest when they spell out mission objectives for the player, and SRW: OG2 is terribly dishonest in that regard.
The unreliable nature of information regarding victory conditions is especially problematic concerning hidden units and items that need to be unlocked. I really like having a large number of hidden things in a game that reward players who are willing to undergo an optional challenge, and I like that SRW:OG2 has so many (and makes them worth the effort), but a big problem with the game is that there are absolutely no in-game hints to their existence, at all. For example, to unlock one hidden unit, you need to have a certain character (Arado) defeat four out of the five available enemies before completing the first phase of mission 19 (among a few other conditions). There is no indication in the game at all that defeating opponents at that time has any importance, let alone is linked to a hidden unit. Further, if you accomplish that objective, there is no indication that have completed a hidden objective. When I first went through the game, I had no idea about the importance of that particular battle, and I never even had any hints at all about the possibility of acquiring that particular hidden unit. Even now on my second playthrough, when I have successfully accomplished the main requirements for getting that unit, I have had no confirmation yet in the game, and I will not until I actually get the unit a few missions from now. Hidden objectives are great, but there needs to be some way for a player to know about their existence without reading a strategy guide or FAQ.
Finally, I want to talk about the Battle Mastery conditions. I think my brother mentioned these before on this blog, and they deserve their own post, but for now I will just say that they are optional objective in each map that have a few problematic interactions with what I have been mentioning above. The Battle Mastery conditions themselves are explicitly laid out (more so than actual victory conditions, which sometimes helps shed some light on how the battle which actually play out), but some conditions work better than others. Namely, there are some missions in which the Battle Mastery condition says something like "Complete this map in 4 turns", even when the main victory condition is deceptive. Because of this, it can be difficult to determine if you are on target or not for achieving the Battle Mastery, and it is easy to end up missing the Battle Mastery entirely because of that confusion. For example, I once mistook the listed victory condition "Bring Seolla down to 30% of her HP" as the actual victory condition, when the actual victory condition is "Defeat All Enemies" (Seolla simply flees the battle when you bring her down to 30%, changing the listed condition). Since the Battle Mastery was "Complete the map by the end of the fifth player phase", the fact that I held back on attacking Seolla because I wanted to complete a hidden objective before the map finished, and avoided targeting the boss because I thought he was optional, resulted in me failing to complete the Battle Mastery objective (which resulted in me going back to play the mission from the start again because I couldn't afford to miss another Battle Mastery while only halfway through the game).
Victory conditions are the guidelines a player uses to help determine how to manage his own time and own preferred way to play a game. Vague and unclear guidelines simply lead to a less fun experience for the player, and should be avoided.