Keep an eye on this thread. ( https://plarium.com/forum/en/throne-kingdom-at-war/598_general-questions/123846_is-this-a-super-pack--mega-pack-or-special-holiday-offer/
)
It has become in essence a communal diary or journal of packs / purchasing collective wisdom and experiences.
e.g. Seems last week's 5 packs (RSS + boosts, silver + boosts, boosts, gold, faith [not shown there]), US$20 each, was an unexpected sale and value purchase. (You note US$20 as possibly being within your budget.)
[I have not seen US$50 or US$100 packs for a -very- long time, if ever.]
[Please post screen shots of such in that thread - I would guess they are mega / super packs, and the thread is struggling with comprehending the extent of whatever value they have vis a vis 'regular' offers.
Pack high points (barring better understanding of mega/super packs), seem to occur every 60'ish days - you can tell when you've hit that point by candle offers exceeding 150 candles, rather than less than 25. Purchasing resets the levels. (So buy everything you can, when you do.)
- so the unexpected sale above is probably only a real 'sale' it you are at this high point at that time.
Note that even those sales don't cover many things you need. e.g. Platinum (for buildings > 26, especially farms), Sixtus candles (same, for studying), Stamina (for jewels to reduce study/build times - 120%) [its absence above is curious], Citadel boosts (OvO winning), and various battle goodies. [Use errands to get order points to get Adrian candles for -120% building.]
- so even arriving at the 'high point' when such sales above are on, you will want to coincide with and purchase one or more of these at that same time.