No Need of RPG Level-up?
When the game is focused more on exploration and challenge, the Level up system has it's merits but the flaws lead directly into the downward slope of difficulty curve. How can the design compensate? Easy. Exploration and upgrades are a major dependent of the Metroidvania format, if you simply rely on these upgrades and most of all reward the player for exploring to find said upgrades, it's a little more delightful to render a Boss as a pushover by leaving no stone unturned as opposed to grinding for an advantage, In my opinion, that is.
I'm completely against this for one reason: it makes fighting enemies pointless. I'm sure most of us here when playing Lament of Innocence, after clearing out a room for the first (mandatory) time, proceeded to simply just run past enemies every other time we went through. Killing enemies in LoI seemed tedious and mostly there to just pad out your own gameplay length because
killing enemies did nothing.
So what would be the point of killing enemies in a Metroidvania with no level-up system? We'd need a way to balance this so that it wouldn't be so boring.
- Do the enemies not respawn? That would make exploration boring simply running through empty rooms.
- Do we switch to a recovery item system similar to Metroid, where rather than having healing items, the enemies drop health instead? I can dig it, but then it seems we're cutting it a bit too close to Metroid.
- Less and weaker enemies to compensate? I wouldn't be behind that because then they'd pose no threat (like in most of SotN)
How about a level-up system, but one akin to FromSoft's Souls games? Killing enemies accumulates EXP, and you spend them at a save point so level up your stats
ever so slightly, and each stat up counts as a Level Up. It'd give a point to actually killing enemies, but the game would still be difficult in comparison. We can even take this a step farther and have you drop your EXP if you're killed.
Classic to Modern power-ups.
Classic jumping in Castlevania is a staple to it's design, and SoTN made that very apparent, Why not have both? you can simply start with the stiff jumping and acquire a power-up that enables the smooth jumping of the Metroidvania games, this can go for subweapons where the II and III tomes can increase the power and speed of subweapons.
Nope. Definitely not. In other areas, this could work (like the aforementioned double/triple-shots) but having actually smooth jumping in a platform game be an upgrade would be bad design. It's even worse if people get used to the stiff-jumping and are suddenly switched the the smooth-jumping and it throws them off completely. One or the other, or even an option. Not both at once.
Other areas of the game where this could work would be:
-Unlocking the ability to extend your whip attack range a la Rondo of Blood (pressing forward twice after attacking)
-Unlocking the ability for an extended slide a la SotN Richter (and have it used for platforming or timed challenges)
-Now, this one might be an unpopular opinion... but an expansion on the Innocent Devil system from CoD. Great concept, bad execution (just like the aforementioned MoF). Have it start off limited like in CoD, but steadily give more options as the game goes on. It's much better than SotN's familiar system which is just a sprite following you and maybe doing something once in a while.
Your other ideas, though, could work just fine. I don't really have much to say on them.
Actual "Pitfalls" in a Metroidvania game, even if it's only on the hardest difficulty.
Remember LOD days where platforming was harder on harder difficulties ie disappearing platforms and the like moved faster? Good times were had... Although OOE did also incorporate some of this too on the harder setting.
Please, no. Pitfalls don't really have a place in games like these. While games like Shantae did have them, they were reserved for outside areas that were purely flat areas, and were never used in dungeons and other areas. If we're talking outside areas, alright, I can get behind that, as long as there's an indicator letting you know "hey, you're gonna die if you fall down here" like Shantae has (because it'd be cheap otherwise).
Also, instant death itself is cheap in these games. Have it do a good chunk of damage and send you back to the beginning of the screen or something. Instant death doesn't belong in a game like this.
Faster moving platforms on higher difficulties would be great, though. Harmony of Despair did this and I
loved it, to the point where playing on normal felt so slow and boring in comparison. I'd love that.
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If there's one thing
I personally want in a Metroidvania, it's either a Continue option or the game just taking you to the last save point immediately when you die. I'm a bit spoiled by modern games but sitting through a game over screen and then being sent back to the main menu only to load my save data up and
then be at my last save point kinda feels extremely tedious. Simply sending you back to the last save point (or even the point when you entered the current area, if we're generous) would dramatically shorten wait time and easily increase the pacing of the game.