Theoretical infinite damage (not just a lot of damage actual infinite)

Here's how you theoretically can actually do infinite damage in the pokemon TCG. 

Step 1: you and your friend build this deck and play against each other (from now on all steps must be completed by both players)

Step 2: draw most of your deck (until you have about 5 cards left)

Step 3: put all the pokemon you have access to in play

Step 4: Use mime jr to copy conkeldur's dynamic punch, shuffling back mime jr with lysanders trump card each time it dies and vs. seeker to get back lysanders trump

Here's how you theoretically can actually do infinite damage in the pokemon TCG. 

Step 1: you and your friend build this deck and play against each other (from now on all steps must be completed by both players)

Step 2: draw most of your deck (until you have about 5 cards left)

Step 3: put all the pokemon you have access to in play

Step 4: Use mime jr to copy conkeldur's dynamic punch, shuffling back mime jr with lysanders trump card each time it dies and vs. seeker to get back lysanders trump card. Repeat until both players are at one prize card left.

Step 5: play gladion to swap with the last prize card(unless your last prize card is already gladion) you now have all the pieces for your combo in deck.

Step 6: put all your pokemon along with your town store in play, your survival brace attached to mime jr, and get comfey in the active with escape board attached.

Step 7: keep cycleing through your deck using lysanders trump card and vs seeker so you never deck out, while doing this use lost blender repeatedly until all of your energy (and town store if the opponent is the one with it in play) are in the lost zone.

Step 8: draw until all your remaining  resources are in your hand or discard pile except lost blender and one other card in deck. Use flower selecting to lost zone the lost blender. Your deck/discard/hand should now only be lysander and vs seeker.

here's where the fun starts!!

Step 9: retreat into the two mime jr and use one to attack the other with conkeldurs counter attack. Then the damaged one will loose its survival brace. On that players turn they will use lysandre to shuffle vs seeker and survival brace into there deck and immediately search out survival brace with town store. Then they heal mime jr with radiant tsereena. Then they attach the survival brace back on the fully healed mime and use counter for 20 more damage.

Step 10: repeat step 9 an infinite amount of times, doing 20 more damage each time so it approaches infinity!!

(if you see any flaws in the list that make it not possible to do infinite damage please comment)
(you could obviously optimate this list with damage modifiers and higher card counts to get to other damage faster but this is the simplest way)