first of all... welcome back yanfly... we miss you and your work

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scripts i want to see in MV
1) Action Battle System like Pearl / XAS and TBS like Gubid
simply because sideview already included in MV... and more option for Battle system is nice...
i also hope people write their battle system using custom scene like Gubid instead overwriting default battle system.
so we can switch battle system at ease.
2) Hopefully Large Event Support (if not supported by default by MV) + Click / Drag Event script
which also compatible with MV mouse / touch screen feature... so we can build game like cooking Mama
Chop onion. drag it to the stove, adjust temperature, stir onion, pour milk, etc

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3) Auto Backup Data script (in ace Tsukihime wrote one).
In case there's a (blue screen / power outage in PC without UPS / Windows hanging) when we save the project and corrupt the project.
(done that two times before i found tsukihime script

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4) MINI GAMES such as fishing script, invader game, card game, slot machine, etc.
so we can build something like Gold saucer of FFVII. place where people spend time to relax when they're a bit tired to resume the story.
edit: or when the developer of the game itself want to refresh.

... after exhausting ourself in creating 100 event... play a bit of minigame can be refreshing
5) Proper resource encryption script. (from the track record... we can assume MV will also have crappy encryption)
simply because all of us don't want our commissioned / original resource got stolen and show up in other people game...
6) Tower Defense Script
event attack other event when entering their range... splash attack, slowing attack, etc
simply because i love tower defence.
7) Event cloner / generator / swapper
so we can spawn event... useful in many ways. for example in ABS to generate enemy... or even creating harvest moon crop system.
or build a city system... and if combined with number two and 6 above... maybe create RTS game
build barrack... train infantry... move infantry... attack enemy... etc
8) GIF / SWF support script.

. (i hope MV already support it but my hope is not too much)
More animation to make our game polished...
since MV using JS... i assume all the current script in ACE need to be "full rewrite" instead "simple porting".

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I'm still not decided will i buy MV as soon as it released or not... because IRL i'm currently busy and don't have time to game dev / script anyway...