I decided to rebirth SMI, because there seems to be alot more mod ideas flowing around. Post your random ideas, generally dumb ideas, great ideas, possibly organize mod ideas for them, etc. Just a little database for some great mod ideas. Get em started! I'll repost with all of my old ones(humongo list) so get ready!
I'll also add polls on if you think certain good and elaborted mod ideas are actually good ideas, which will be established periodically if you guys want. But anyways, I'll probably post a new post which will be a database of all past mod ideas...I'll have to recheck and categorize the old topic, but hopefully this topic won't die. 
Here it is! My basic database!
The Legendary Medieval Mod Idea(lol as if)
VEHICLES-
Banshee-Dragon... not to big, just a basic dragon about the size of the banshee... the fuel rod gun is red instead of green, and the normal plasma fire is changed to spikes coming out of the dragon.
Scorpion-Trebuchet... the same stats for the scorpion except it looks like a steel catapult/trebuchet(look at Edwin's definition of the trebuchet on page 3). The scorpions cannon is changed to a big rock flying out of the catapult, except the speed that it travels is reduced by half, but there is more area of effect and higher damage.The life span of this bolt would last across the entire map.The scorpions machine gun is changed to tiny rocks flying out of the catapult that have an area of effect, a little bit higher damage, but travel 1/4 slower.
Rocket Warthog-Ballista... the warthog moves only a bit faster than the tank, but looks like a ballista, which is tringular, has a couple of wires attached to the spear ready to shoot. Of course, the warthogs rockets are changed to look like giant spikes(Maybe an enlarged version of the dragons spikes) and require 1 second reloading after every shot, and at the end of FIVE shots you have to have a 3 second reload. It would have a wider area of effect, more damage, and the life span of these bolts would last across the entire map.
Machine Gun Warthog-Catapult... Looks like a smaller version of the scorpion/trebuchet, but shoots only the tiny rocks and no big ones. It would also move a little bit faster than the ballista. The tiny rocks would still move slower, but not as slow as the tanks, and would have an area of effect and more damage.
Ghost-Battering Ram... shoots trees with a tiny area of effect but the same damage, and a force of 5. The only diference in looks is that its color is brown.
WEAPONS-
Human Assault Rifle-Knives-Pretty much you rapid fire tiny knives with a little bit more damage than normal assault rifle but decreased speed.
Pistol-Crossbow-Looks like a crossbow.Has a much slower fire speed, but the clip of the human AR, alot more damage, alot more range, and less scatter and better accuracy.
Sniper-The Super Bow-Same stats as the sniper rifle, just looks like a bow and shoots arrows.
Fuel Rod Gun-Knife Shower-Has same stats as the fuel rod gun except it shoots comepletely straight, looks like a bow, and shoots about 5 knives per shot.
Rocket Launcher-Portable Miniature Ballista- Has the same stats as the ballista except it only has ONE shot before reloading, 8 shots in all, and looks like the turret on the back of the ballista.
Covenant Assault Rifle-Shoots tiny rocks, but the texture is just a stone version of the Covenant Assault Rifle.
Plasma Pistol-Sword-IF POSSIBLE,the plasma pistol would be replaced by a plasma sword, which would just be changed from blue to grey.If not possible, I'll think of something later.
Shade-Ballista Turret-This would have to be put into bloodgulch,2 on top of each base, one in the back and one in the front of the base. This would have the same stats as the ballista except it would only shoot 3 rounds until it had to reload and would look like the turret of the ballista.
Bases-Castle... Only difference is that its made of stone and it has a door on all entrances that can be damaged only by the siege equipment and not weapons. The doors could be made destructable if its just logs in front of all four castle entrances that respawn every 30 seconds when destroyed. You can spawn only on the top of your castle, if possible.
Map-Trees are changed to stone blocks and the grass is black.
SOUNDS-MOVEMENT :
Banshee-Sounds more like a growling banshee than a high pitched squeal. It sounds almost like the fuel rod gun colliding with a vehicle except not as high pitched, and continous when turning.
Scorpion-Sounds like gears creaking and an occasional small cracking sound.
Rocket Warthog- Same as the scorpion except higher pitched.
LAAG Gun Warthog-Same as the scorpion, just not as loud.
Ghost-Sounds like the breaking of a branch occasionally.
SOUNDS-FIRING :
Banshee-Fuel Rod Gun- Sounds like fire, like the explosion at the beginning of POA.Normal Plasma Fire- Sounds like crunching.
Scorpion-Cannon-Sounds like a wire snapping.Machine Gun Fire-Sounds the same as the normal scorpions machine gun fire.
Rocket Warthog-Sounds just like the scorpion cannon sound.
LAAG Gun Warthog-You know when you throw a grenade at a rock and all that gravel comes out? The sound of the gravel on the ground is for this.
Ghost-Sounds the same as the movement.The sound of a branch breaking.
Human Assault Rifle-Sounds normal, except has a more metalic sound like steel clashing on steel.
Pistol-Sounds like TWANG!
Sniper-Sounds the same as the pistol.
Fuel Rod Gun-Sounds the same as the Human Assault Rifle.
Rocket Launcher- Sounds the same as the Rocket Warthog.
Covenant Assault Rifle- Sounds the same as the scorpion machine gun.
Plasma Pistol-sounds like hitting air.
Shade-Sounds just like the scorpion cannon sound.
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I'm thinking that ( if it's even possible...I BET IT ISN'T!!!!!!!!! ) We should swap plasma grenades graphic to one of a grunt just hit by a grenade... dead and flying.. It would be funny to see grunts flying threw the air yelling and sticking onto people and blowing up. KHAMIKAZI GRUNTS!!!!
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This time I think of a shockwave wep. Pretty much its a weapon that you shoot, does only 10 dmg, but has a high force... being able to knock over vehicles on the run, shoot people into the air, and if you shoot near yourself give yourself a jumpstart to chase after an enemy. This weapon would be best for CTF, should be fairly simple to make, and would be extremely effective.
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The Wraith Turret- A mod of the covenant shade turret, it shoots wraith tank plasma bolts, 1 per second, with a boost in the speed that the rounds fly.
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The Sniper Tank-A mod of the Scorpion, this tank shoots its cannon, but the cannon has no area of effect, but also no reload time in place of the machine gun. The normal tank blast with reload is also there.It also is more armored, with much more protection.
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The Banshog- A banshee crossed with a warthog, the banshee has weels... so that it wouldn't crash, , could drive on the ground, and could fly straight off a hill without getting hurt.
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The Camoshee- A banshee with active camo, increased speed, and no fuel rod gun. A fast invisible banshee that can run people over. A personal flying assassin.
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The chain gun- Shoots 50 rounds per second, but only has 200 ammo per reload. Shoots for 4 seconds but would be the best gun for up close combat.
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Tree Launcher- Launches a tree with 2 fuel rod gun bolts sticking too it, and it explodes with christmas cheer, instantly showing a green plasma burn on the ground and red blood.
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Blow Up Santa- A mod of the Shade,looks like Santa's bag, has primary and secondary fire....primary fire shoots a red MC with white lining on waist and around head with a reload time of 4 seconds...secondary fire shoots tiny presents with no reload at the speed of shade bolts.
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Jingle Banshee- Looks like a jingle bell, shoots normal fuel rod gun but red normal plasma fire.
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Ghost...of Christmas Future!- A mod of a ghost to make it black, has a sythe sticking out the side, and shoots sythes.
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The Orinament Frag- A mod of the frag grenade, is made to look like a christmas orniment ball, and blows up with a shower of green and red confetti.
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The Glowing Angel Sprite of Doom- An angel gone bad.A mod of the plasma grenade to be black and to have tiny red wings sticking out of it, it blows with 3x the force, no explode delay, and a fast throw.
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But with that mod make the banshee's fuel rod shoot Barnie and the Rocket Warthog turns into Dora the Explorer running with a couple of rocket launchers on the back, while the driver is one the left side of her head, side side or the right, and TWO back seats, one holding one rocket launcher on each of Dora's shoulder. Add that with the teletubbies and make everything pink and it would be hilarious.
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FPVIST(First Person View Invisible Sniper Turret)- Pretty much you get rid all the shades and replace them with invisible warthogs that can't move. When you get into the LAAG turret in the back, you instantly go invisible with a first person view on the LAAG turret. The turret shoots sniper rounds and zooms 2x and 8x, and reloads after 8 shots of stealth killing.
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This would be best for danger canyon....
How about travel mod? Sort of like the teleporter except there are 5 teleporters, and they can only be used in a window of 10 seconds for 1 minute. There are different climate zones(ones raining, ones sunny, anothers snowing, another is hailing, and the other is foggy. There would be 11 teleporters in all, and your bases teleporter would teleport to your side of the climate,while the enemies teleporter goes to the other side of the climate zone. There would be one secret teleporter hidden inside a cave which teleports you to a high area thats very very dark. Each hosts the best weapons for each condition.The sniper rifle is in the foggy climate, the assault rifle and pistol for the raining climate, the fuel rod gun and the rocket launcher for the snowing climate, the hailing climate hosts the plasma rifle and plasma pistol, and the sunny climate has the needler, pistol, and plasma pistol.The dark area would have the sniper rifle, pistol, and rocket launcher, which is all the weapons that can zoom and do some damage.
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I don't think this is possible because it would be really laggy probably but it would be so cool if it was.
Grunt....Es., Grunt. Espionage Grunt....it would be funny, lol...you fight against like 25 marines and you have 5 blue elites on your side along with 25 grunts, since grunts are so weak. It would be a challenge, but it would be fun. Probably would take forever and isn't original, but you being a grunt assassin working for ever pays the most covie credits wins, so you can have a mission to wack some gold elite in the back or some mission (like the last level...) to have to go through all the obstacles to kill the mother of the flood, which would be a tottaly oversized infection form that can kill anything in one hit. But hey, your invisible... even if there are 20 combat forms around it, sneak past them and shoot and shoot and shoot that mother infection form to death and the end movie would be the ship blowing up , and you fly away in a covie dropship instead of a Longsword with the MC...
Um...yeah. Not possible. But hey.
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Covenant Rifle - It would be a really fast moving pinpoint of red light with a contrail....that explodes in a plasma burst in sync with contact. Since it's a 1 hit kill, it has 2 shots before overheat and a 3 second cooldown. It has a full charge of 45.
mp conversion.