Is Vampirism a status effect, and does it stack?
It does. But the effect is rather weak, so I don't feel like it can become OP unless you get a Retort or something like that and drink 10+ such potions.
I have also changed the Vampire Sword to give you HP on every hit instead of kill. It makes it much more enjoyable to use, especially in co-op where you don't have to yell at your ally for dealing the final blows to enemies
Maybe it slowly loses you health (speed similar to hunger) if you have the effect active on any of the outdoor levels (1, 2, 6, 7) without a darkness scroll/staff activated.
That would be reasonable and very cool, but somehow I find such complicated mechanics hard to explain to players, esp. since I like to keep the text for potion effects as short as possible. It would also be good to prevent players getting HP from bloodless enemies (skeletons, slimes, etc.). If only the game were full RPG, I would have added all the complex mechanics on top as well.
I like the sound of confidence - again, stacking?
Yes, +20% to all skills per potion. But only active while you're full HP.
It makes a nice decision dilemma when you're almost at full health and don't want to spend a healing potion to heal, say 3HP, but doing so would give you a +60% damage boost for example.
Regarding the sticky bombs... I wonder if having a pet that dropped what are basically mines would work, where they go off as soon as an enemy walks onto them? (Or even an enemy or friend, if you wanted to make them a bit more dangerous!)
I feel like it might be hard to track if they went off immediately. Maybe a combination would be a good idea: a pet places them on the ground and they are inactive until an enemy walks into the bomb. Then it glues to the enemy and starts ticking and explodes a couple of seconds later.
I guess I'll have to add it to the game and test to see what feels the best.
120 gold really feels a lot for something that only affects one room, gives no permanent bonus, and can't be used on bosses, but that may just be me?
Initial idea was to be able to use it on a boss as well. But then I tried to play a couple of games with it and the attack speed of the Bushido stun-locks all the small boss types (violent knights, trickster, dragon master, etc.) to the point the boss fights become trivial (esp. if you summon two of them in the same room).
The main use is if you get into late game (ice, desert) with low damage output, but have a lot of gold (it's usually in the 1500-3000 range for me) that you cannot spend otherwise anyway. So, summoning those to get through some tough rooms can be a life saver.
Maybe I should lower the price. It needs testing, of course.