1. you can get an opaniel weapon by "simply" enhancing a chimera weapon +12 and exchange it for talis then +12 that weapon and exchange for opaniel
you can also obtain an opaniel ticket from blessed/premium tjb
blessed requires 10 time jewels and novice unique pres stone
premium requires 15 time jewels and novice ancient pres stone
if you obtain an opaniel exchange ticket you can use a lvl 1 weapon (of the type of weapon you wish to recieve ex. lvl 1 dagger+opaniel exchange = opaniel dagger)

to transcend this you need to obtain a shiny transcendence stone which can be done various ways
1. run power arena and obtain winners prize and save up 40 badge of victory to exchange for a shiny
2. you can obtain transcendence stone fragments from mirror dungeon quests (1000 of these = 1 transcendence stone and you need 40 transcendence stones to get a shiny)
3. you can farm rough transcendence stones from mirror mobs (each one of these is exchanged for 3 transcendence stone fragments)
4. run the risk of someone trying to scam you and "purchase" one from an in game player

2. you need to use the same method as any other craft item in game weapon reinforcement stones and pres abradents to keep it from breaking

3. you can use in game stones from the ip mall to equip on your weapon (these last 3 days)
or you can purchase stones from the IM depending on the stat amount and duration will depend on the pricing
you can also farm these weapon options again from mirror dungeons

i hope that helps and sorry if i missed any other methods of obtaining and enhancing