Celeste did not recieve any changes in patch 2.0 but a new counter to her has appeared, in the form of Idris. Her playstyle and place in the meta will not change much however, you will have to get used to the new items and lack of jungle shop. Her new playstyle will have to have a new rotation. For me, i like to clear the first wave and rotate as usual. Make the most of what you can in the first four minutes. Most people I've seen have become more wary and not invade in the first few minutes due to the changes, even if the changes did not affect the time frame. Try to push an advantage and steal two rotations in this time, otherwise, just keep farming as it will be farmfest after the fourth minute and most fights will now break out in the lane, if any at all. Your farm will thus have a higher chance of being affected as a result. Try caution pinging your allies to not fight if your farm is still alive. Get the message across that you wish to push before skirmishing. This will save your farm and give you a minor extra minion damage in a fight.
Other than that, Jungle Celeste will be much more viable and easy to use for the least experienced Celeste. Usually, Jungle Celeste needs to be experienced in order to not feed the jungle away. Celeste's farm will be secured in the jungle from minute 4. This means that those not confident of holding their ground in the jungle will still be able to use jungle celeste.
The new items have a decent effect on Celeste. Poisoned Shiv is Weapon and will have literally zero effect on Celeste, unless you decide to go WP celeste, which can
work but i have only ever won once with it in a ranked, when i was in Decent-ish(T4). You probably will not build Nullwave Gauntlet unless you have some game plan in mind with your team but it won't increase your damage and other items give more survivabilty. It probably won't be used for you either as the roams items are of higher priority. It CAN **** your mind up if it is used on you together with an afterburn or something however. Be careful of that and play more cautiously if its used on you.
The items that matter to Celeste are Echo and Slumbering Husks. Both items revolve around burst. If you require lots of burst damage, buy an Echo as your fourth offensive item. Echo requires the base damage to be decent. After your two core items, the damage is still simply not enough to warrant an echo and a extra FB, SG, BM or CW is needed before Echo can be built. Buying Echo can give you immense burst and snipe damage. However, in a long term fight, an extra defense, SG, BM or CW will give you more overall damage.
Slumbering Husk is one of the main highlights of this update to me. It literally grants you near immunity to burst for a few seconds.
Against Taka, Kestrel or any other burst hero? BUY THIS ITEM. This item basically grants you fortified health if you took a sudden burst of damage. What this means is that it will protect you temporarily with extra defense iirc for the next few seconds. Did a Kestrel OSOK always take 70% of your health away? Look, it now only does 30%. For those familiar with Black King Bar in DotA, this fortified health is similar to a sudden spike of defense for a duration. It is triggered by a burst of damage and cannot be self-activated. The reason i made the reference is due to the fact you can use SH like BKB: Go ham when it is activated. When it is activated, you can just sit there and keep dealing your damage. All damage done to you is basically halved. Too bad it does not have magic immunity but oh well. If is is activated prematurely, wait its cooldown out. It is around a 30 sec cooldown and is able to be triggered by a visual sign of a green algae-ish colour aura on your feet. Make sure that its avaliable before the fight starts as it is a life-saver.