Vamp already answered most of them already.

Go alone or in a team?

Both. Some times depends on if team can combo sometimes its good to split team up, but if you go to a high area team work helps cause more damage equal more exp as well as it distributes the damage done to you. So less likely to be combed upon, mean less damage you take.

Burst there or not burst there?

Don't burst there. I don't see why some people do it, it seems a waste but that's also your choice in the end.

Go with pet?

Best for pets I think cause they lvl as fast as you. Also good for pets with sucky HP starting like niss, Lan, elin, etc... The mobs on TI doesn't hi hard and their HP is also low as well making it faster and easir to kill.

Go on 2x exp days?

ONLY worth it to go on double exp days. Also like vamp mentioned, you should use pots. The higher the better.

Go with best eq?

Always best to train nakie just in case where you go doesn't breaks your items, also like vamp mentioned. It depends on where you train so ALWAYS keep the lvl 19+ rule in mind especially if you feel you wish to wear gear. prolly best to use cheap DEF gear if you think you will die.

Go to train skills (attack to hit to beating)or just kill the mob as fast as u can?

I always like to train skills there, because it heals your SP so if you don't have an e-remote to use soul dodge training skill on TI is always useful. To get the most out of the voucher try using the first 4-5 hours to train and then the last 1-2 hour to train skills. (If you are using a 6hour voucher)

Go with DEF-based eq or ATK-based eq? (+pet eq)

I mentioned above DEF gear, because if you think your HP sucks and you die often. Also if you want to use ATK gear to help you will your attack that's fine too, but DEF serves a better purpose. Only use cheap gear you can easily replace or easy to compound incase they break. DON'T go with IMs.

Go there now or lvl a bit more? (im lvl 44 now)

Go anytime you want. If you feel you will never burst anytime soon then go now. But if you plan to burst I say wait till after RB so you get the most out of it (also like vamp mentioned).

Note: If you use up that free vouchers you got from "Gifts For Leveling" then don't worry you will always get more from drop events from lvl 10+ monsters. So keep your eye out from events like that. If you see a system prompt pop up with a mention of killing lvl 10+ monsters then go on the website and check to see what the drops contain and if its worth it.

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